diff --git a/dev/examples.php b/dev/examples.php
index b83f0d25..708b4ede 100644
--- a/dev/examples.php
+++ b/dev/examples.php
@@ -10,14 +10,14 @@
 use UnitConverter\Calculator\SimpleCalculator;
 use UnitConverter\Registry\UnitRegistry;
 use UnitConverter\Unit\AbstractUnit;
-use UnitConverter\Unit\Length\Centimeter;
+use UnitConverter\Unit\Length\Centimetre;
 use UnitConverter\Unit\Length\Inch;
 
 # Configuring a New Converter
 # ===========================
 
 $units = array(
-  new Centimeter,
+  new Centimetre,
   new Inch,
 );
 
diff --git a/src/UnitConverter/Unit/Length/Centimeter.php b/src/UnitConverter/Unit/Length/Centimetre.php
similarity index 85%
rename from src/UnitConverter/Unit/Length/Centimeter.php
rename to src/UnitConverter/Unit/Length/Centimetre.php
index 5766f23d..552e910d 100644
--- a/src/UnitConverter/Unit/Length/Centimeter.php
+++ b/src/UnitConverter/Unit/Length/Centimetre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Centimeter data class.
+ * Centimetre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Centimeter extends LengthUnit
+class Centimetre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("centimeter")
+            ->setName("centimetre")
 
             ->setSymbol("cm")
 
diff --git a/src/UnitConverter/Unit/Length/Decimeter.php b/src/UnitConverter/Unit/Length/Decimetre.php
similarity index 86%
rename from src/UnitConverter/Unit/Length/Decimeter.php
rename to src/UnitConverter/Unit/Length/Decimetre.php
index 58e241ed..77a578fb 100644
--- a/src/UnitConverter/Unit/Length/Decimeter.php
+++ b/src/UnitConverter/Unit/Length/Decimetre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Decimeter data class.
+ * Decimetre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Decimeter extends LengthUnit
+class Decimetre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("decimeter")
+            ->setName("decimetre")
 
             ->setSymbol("dm")
 
diff --git a/src/UnitConverter/Unit/Length/Kilometer.php b/src/UnitConverter/Unit/Length/Kilometre.php
similarity index 86%
rename from src/UnitConverter/Unit/Length/Kilometer.php
rename to src/UnitConverter/Unit/Length/Kilometre.php
index fb9ab9de..5c9f7c70 100644
--- a/src/UnitConverter/Unit/Length/Kilometer.php
+++ b/src/UnitConverter/Unit/Length/Kilometre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Kilometer data class.
+ * Kilometre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Kilometer extends LengthUnit
+class Kilometre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("kilometer")
+            ->setName("kilometre")
 
             ->setSymbol("km")
 
diff --git a/src/UnitConverter/Unit/Length/LengthUnit.php b/src/UnitConverter/Unit/Length/LengthUnit.php
index ced6ac89..5c0a0237 100644
--- a/src/UnitConverter/Unit/Length/LengthUnit.php
+++ b/src/UnitConverter/Unit/Length/LengthUnit.php
@@ -30,5 +30,5 @@ abstract class LengthUnit extends AbstractUnit
 {
     protected $unitOf = Measure::LENGTH;
 
-    protected $base = Meter::class;
+    protected $base = Metre::class;
 }
diff --git a/src/UnitConverter/Unit/Length/Meter.php b/src/UnitConverter/Unit/Length/Metre.php
similarity index 82%
rename from src/UnitConverter/Unit/Length/Meter.php
rename to src/UnitConverter/Unit/Length/Metre.php
index e8af3fe7..6fcc2d79 100644
--- a/src/UnitConverter/Unit/Length/Meter.php
+++ b/src/UnitConverter/Unit/Length/Metre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Meter data class. All units of Length are based off of Meter.
+ * Metre data class. All units of Length are based off of Metre.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Meter extends LengthUnit
+class Metre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("meter")
+            ->setName("metre")
 
             ->setSymbol("m")
 
diff --git a/src/UnitConverter/Unit/Length/Micrometer.php b/src/UnitConverter/Unit/Length/Micrometre.php
similarity index 86%
rename from src/UnitConverter/Unit/Length/Micrometer.php
rename to src/UnitConverter/Unit/Length/Micrometre.php
index af31414a..504ef3f9 100644
--- a/src/UnitConverter/Unit/Length/Micrometer.php
+++ b/src/UnitConverter/Unit/Length/Micrometre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Micrometer data class.
+ * Micrometre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Micrometer extends LengthUnit
+class Micrometre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("micrometer")
+            ->setName("micrometre")
 
             ->setSymbol("µm")
 
diff --git a/src/UnitConverter/Unit/Length/Milimeter.php b/src/UnitConverter/Unit/Length/Millimetre.php
similarity index 85%
rename from src/UnitConverter/Unit/Length/Milimeter.php
rename to src/UnitConverter/Unit/Length/Millimetre.php
index 6451984c..5e1e4612 100644
--- a/src/UnitConverter/Unit/Length/Milimeter.php
+++ b/src/UnitConverter/Unit/Length/Millimetre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Milimeter data class.
+ * Millimetre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Milimeter extends LengthUnit
+class Millimetre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("milimeter")
+            ->setName("millimetre")
 
             ->setSymbol("mm")
 
diff --git a/src/UnitConverter/Unit/Length/Nanometer.php b/src/UnitConverter/Unit/Length/Nanometre.php
similarity index 86%
rename from src/UnitConverter/Unit/Length/Nanometer.php
rename to src/UnitConverter/Unit/Length/Nanometre.php
index 65d61068..7b330916 100644
--- a/src/UnitConverter/Unit/Length/Nanometer.php
+++ b/src/UnitConverter/Unit/Length/Nanometre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Nanometer data class.
+ * Nanometre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Nanometer extends LengthUnit
+class Nanometre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("nanometer")
+            ->setName("nanometre")
 
             ->setSymbol("nm")
 
diff --git a/src/UnitConverter/Unit/Length/Picometer.php b/src/UnitConverter/Unit/Length/Picometre.php
similarity index 86%
rename from src/UnitConverter/Unit/Length/Picometer.php
rename to src/UnitConverter/Unit/Length/Picometre.php
index 489c6736..e240a2c2 100644
--- a/src/UnitConverter/Unit/Length/Picometer.php
+++ b/src/UnitConverter/Unit/Length/Picometre.php
@@ -15,18 +15,18 @@
 namespace UnitConverter\Unit\Length;
 
 /**
- * Picometer data class.
+ * Picometre data class.
  *
  * @version 1.0.0
  * @since 0.0.1
  * @author Jordan Brauer <jbrauer.inc@gmail.com>
  */
-class Picometer extends LengthUnit
+class Picometre extends LengthUnit
 {
     protected function configure (): void
     {
         $this
-            ->setName("picometer")
+            ->setName("picometre")
 
             ->setSymbol("pm")
 
diff --git a/tests/unit/UnitConverter/Registry/UnitRegistry.spec.php b/tests/unit/UnitConverter/Registry/UnitRegistry.spec.php
index e6f11e65..9284083b 100644
--- a/tests/unit/UnitConverter/Registry/UnitRegistry.spec.php
+++ b/tests/unit/UnitConverter/Registry/UnitRegistry.spec.php
@@ -18,26 +18,26 @@
 use UnitConverter\Registry\UnitRegistry;
 use UnitConverter\Unit\UnitInterface;
 use UnitConverter\Unit\AbstractUnit;
-use UnitConverter\Unit\Length\Centimeter;
+use UnitConverter\Unit\Length\Centimetre;
 use UnitConverter\Unit\Length\Inch;
-use UnitConverter\Unit\Length\Meter;
-use UnitConverter\Unit\Length\Milimeter;
+use UnitConverter\Unit\Length\Metre;
+use UnitConverter\Unit\Length\Millimetre;
 
 /**
  * @coversDefaultClass UnitConverter\Registry\UnitRegistry
  * @uses UnitConverter\Registry\UnitRegistry
  * @uses UnitConverter\Unit\AbstractUnit
  * @uses UnitConverter\Unit\Length\Inch
- * @uses UnitConverter\Unit\Length\Centimeter
- * @uses UnitConverter\Unit\Length\Meter
- * @uses UnitConverter\Unit\Length\Milimeter
+ * @uses UnitConverter\Unit\Length\Centimetre
+ * @uses UnitConverter\Unit\Length\Metre
+ * @uses UnitConverter\Unit\Length\Millimetre
  */
 class UnitRegistrySpec extends TestCase
 {
     protected function setUp ()
     {
         $this->registry = new UnitRegistry(array(
-            new Centimeter,
+            new Centimetre,
             new Inch,
         ));
     }
@@ -173,7 +173,7 @@ protected function configure () : void
                     ;
             }
         });
-        $this->registry->registerUnits([new Meter, new Milimeter]);
+        $this->registry->registerUnits([new Metre, new Millimetre]);
 
         $this->assertTrue($this->registry->isUnitRegistered("sP"));
         $this->assertTrue($this->registry->isUnitRegistered("m"));
diff --git a/tests/unit/UnitConverter/Unit/AbstractUnit.spec.php b/tests/unit/UnitConverter/Unit/AbstractUnit.spec.php
index 191260af..0015285e 100644
--- a/tests/unit/UnitConverter/Unit/AbstractUnit.spec.php
+++ b/tests/unit/UnitConverter/Unit/AbstractUnit.spec.php
@@ -18,7 +18,7 @@
 use UnitConverter\Measure;
 use UnitConverter\Unit\AbstractUnit;;
 use UnitConverter\Unit\Length\Inch;
-use UnitConverter\Unit\Length\Meter;
+use UnitConverter\Unit\Length\Metre;
 
 /**
  * @coversDefaultClass UnitConverter\Unit\AbstractUnit
@@ -35,7 +35,7 @@ protected function setUp ()
             protected $symbol = "sP";
             protected $scientificSymbol = "Ω·m";
             protected $unitOf = Measure::LENGTH;
-            protected $base = Meter::class;
+            protected $base = Metre::class;
             protected $units = 9001;
         };
     }
diff --git a/tests/unit/UnitConverter/UnitConverter.spec.php b/tests/unit/UnitConverter/UnitConverter.spec.php
index 0a151c05..f698e08c 100644
--- a/tests/unit/UnitConverter/UnitConverter.spec.php
+++ b/tests/unit/UnitConverter/UnitConverter.spec.php
@@ -18,7 +18,7 @@
 use UnitConverter\UnitConverter;
 use UnitConverter\Calculator\SimpleCalculator;
 use UnitConverter\Registry\UnitRegistry;
-use UnitConverter\Unit\Length\Centimeter;
+use UnitConverter\Unit\Length\Centimetre;
 use UnitConverter\Unit\Length\Inch;
 
 /**
@@ -28,7 +28,7 @@
  * @uses UnitConverter\Calculator\SimpleCalculator
  * @uses UnitConverter\Registry\UnitRegistry
  * @uses UnitConverter\Unit\AbstractUnit
- * @uses UnitConverter\Unit\Length\Centimeter
+ * @uses UnitConverter\Unit\Length\Centimetre
  * @uses UnitConverter\Unit\Length\Inch
  */
 class UnitConverterSpec extends TestCase
@@ -37,7 +37,7 @@ protected function setUp ()
     {
         $this->converter = new UnitConverter(
             new UnitRegistry(array(
-                new Centimeter,
+                new Centimetre,
                 new Inch,
             )),
             new SimpleCalculator