keen
(chiefly Commonwealth) Showing a quick and ardent responsiveness or willingness; eager, enthusiastic, interested.
Fierce, intense, vehement.
Having a fine edge or point; sharp.
Acute of mind, having or expressing mental acuteness; penetrating, sharp.
Of cold, wind, etc.: cutting, penetrating, piercing, sharp.
(Britain) Of prices, extremely low as to be competitive.
(US, informal, dated) Marvelous.
(obsolete) Brave, courageous; audacious, bold.
(rare) To make cold, to sharpen.
A prolonged wail for a deceased person.
To utter with a loud wailing voice or wordless cry.
To mourn.