Merriam-Webster Collegiate Dictionary - annual

 I. adjective  Etymology: Middle English, from Anglo-French & Late Latin; Anglo-French annuel, from Late Latin ~is, blend of Latin annuus yearly (from annus year) and Latin annalis yearly (from annus year); probably akin to Gothic athnam (dative plural) years, Sanskrit atati he walks, goes  Date: 14th century  1. covering the period of a year ~ rainfall  2. occurring or happening every year or once a year ; yearly an ~ reunion  3. completing the life cycle in one growing season or single year ~ plants  • ~ly adverb  II. noun  Date: 14th century  1. an event that occurs yearly  2. a publication appearing yearly  3. something that lasts one year or season; specifically a plant that completes its life cycle in one growing season