[keen] adj [ME kene brave, sharp, fr. OE cene brave; akin to OHG kuoni brave] (13c) 1 a: having a fine edge or point: sharp "a ~ sword" b: affecting one as if by cutting "~ sarcasm" c: pungent to the sense "a ~ scent"
2. a (1): showing a quick and ardent responsiveness: enthusiastic "a ~ swimmer" (2): eager "was ~ to begin" b of emotion or feeling: intense "the ~ delight in the chase --F. W. Maitland" 3 a: intellectually alert: having or characteristic of a quick penetrating mind "a ~ student" "a ~ awareness of the problem"; also: shrewdly astute "~ bargainers" b: sharply contested "~ debate" c: extremely sensitive in perception "~ eyes"
4: wonderful, excellent syn see sharp, eager -- keen.ly adv -- keen.ness n
[2]keen n (1830): a lamentation for the dead uttered in a loud wailing voice or sometimes in a wordless cry [3]keen vb [Ir caoinim I lament] vi (1845) 1 a: to lament with a keen b: to make a sound suggestive of a keen
2: to lament, mourn, or complain loudly ~ vt: to utter by keening -- keen.er n