Merriam-Webster's Collegiate® Dictionary, 11th Edition
HUMOR
I. noun
Etymology: Middle English humour, from Anglo-French umor, umour, from Medieval Latin & Latin; Medieval Latin humor, from Latin humor, umor moisture; akin to Old Norse vǫkr damp, Latin humēre to be moist, and perhaps to Greek hygros wet
Date: 14th century
1. a normal functioning bodily semifluid or fluid (as the blood or lymph), a secretion (as a hormone) that is an excitant of activity,
2. a fluid or juice of an animal or plant, characteristic or habitual disposition or bent ; temperament , an often temporary state of mind imposed especially by circumstances , a sudden, unpredictable, or unreasoning inclination ; whim ,
3. that quality which appeals to a sense of the ludicrous or absurdly incongruous, the mental faculty of discovering, expressing, or appreciating the ludicrous or absurdly incongruous, something that is or is designed to be comical or amusing, see: wit
II. transitive verb (humored; humoring)
Date: 1588
to soothe or content by indulgence, to adapt oneself to, see: indulge