noun

1. an adapting or being adapted
2. a thing resulting from adapting this play is an adaptation of a novel
3. a change in structure, function, or form that improves the chance of survival for an animal or plant within a given environment
4. the natural reactions of a sense organ to variations in the degree of stimulation
5. Sociology a gradual change in behavior to conform to the prevailing cultural patterns

Etymology: Fr < ML adaptatio: see adapt