Add terminology section to README.md

README.md

@@ -99,6 +99,19 @@ generate_deciles_charts:
 | `tables.output`          | Generate a deciles table for each measure table that is matched by the `--input-files` glob pattern |
 | `charts.output`          | Generate a deciles chart for each measure table that is matched by the `--input-files` glob pattern |
 
+## Terminology
+
+**Measure table**<br>
+Generated by cohort-extractor's `generate_measures` function;
+contains data for one measure for *all* index dates in a range
+(a *partial* measure table contains data for one measure for *one* index date in a range)
+
+**Deciles table**<br>
+Derived from a measures table
+
+**Deciles chart**<br>
+Derived from a deciles table
+
 ## Notes for developers
 
 Please see [_DEVELOPERS.md_](DEVELOPERS.md).