Merriam-Webster Collegiate Dictionary - may

 I. noun  Etymology: Middle English, from Anglo-French & Latin; Anglo-French mai, from Latin Maius, from Maia, Roman goddess  Date: 12th century  1. the fifth month of the Gregorian calendar  2. often not capitalized the early vigorous blooming part of human life ; prime  3. the festivities of ~ Day  4. not capitalized  a. green or flowering branches used for ~ Day decorations  b. a plant that yields may: as  (1) hawthorn  (2) a spring-flowering spirea  II. biographical name Sir Thomas Erskine 1815-1886 1st Baron Farnborough English jurist MAY  I. verbal auxiliary  (past might; present singular & plural ~)  Etymology: Middle English (1st & 3d singular present indicative), from Old English m?g; akin to Old High German mag (1st & 3d singular present indicative) have power, am able (infinitive magan), and perhaps to Greek mechos means, expedient  Date: before 12th century  1.  a. archaic have the ability to  b. have permission to you ~ go now ; be free to a rug on which children ~ sprawl — C. E. Silberman — used nearly interchangeably with can  c. — used to indicate possibility or probability you ~ be right things you ~ need — sometimes used interchangeably with can one of those slipups that ~ happen from time to time — Jessica Mitford — sometimes used where might would be expected you ~ think from a little distance that the country was solid woods — Robert Frost  2. — used in auxiliary function to express a wish or desire especially in prayer, imprecation, or benediction long ~ he reign ~ the best man win  3. — used in auxiliary function expressing purpose or expectation I laugh that I ~ not weep or contingency she'll do her duty come what ~ or concession he ~ be slow but he is thorough or choice the angler ~ catch them with a dip net, or he ~ cast a large, bare treble hook — Nelson Bryant  4. shall, must — used in law where the sense, purpose, or policy requires this interpretation  Usage: see can  II. noun  Etymology: Middle English, from Old English m?g kinsman, kinswoman, maiden  Date: before 12th century archaic maiden