Definition of rationality in US English:
rationality
nounˌraSHəˈnalədēˌræʃəˈnælədi
1The quality of being based on or in accordance with reason or logic.
like any phobia, rationality plays only a small role
- 1.1 The quality of being able to think sensibly or logically.
Scott wanted to play the character with a bit more dignity and rationality
- 1.2 The quality of being endowed with the capacity to reason.
we call rationality the distinction of man, when compared with other animals
2Mathematics
The property of a number, quantity, or expression of being expressible, or containing quantities which are expressible, as a ratio of whole numbers.