having or showing eagerness or enthusiasm

a keen gardener

John was keen to help

(of a sense) highly developed

I have keen eyesight

(of the edge or point of a blade) sharp

the keen blade went through the weeds

(of activity or feeling) intense

there could be keen competition to provide the service

excellent

I would soon fly to distant stars—how keen!

wail in grief for a dead person

the body of Johnny was taken by his own people who keened over him

an Irish funeral song accompanied by wailing in lamentation for the dead