Meaning of “keen” - Learner’s Dictionary

keen

adjective uk us /kiːn/
INTERESTED

B1 very interested or enthusiastic:

He's very keen on travelling.
WANTING TO DO

B1 wanting to do something very much:

VERY GOOD

very good or well developed:

a keen sense of smell
keenness noun [ U ]
keenly adverb

(Definition of “keen” from the Cambridge Learner’s Dictionary © Cambridge University Press)