adj. hap·pi·er, hap·pi·est
1. Enjoying, showing, or marked by pleasure, satisfaction, or joy. See Synonyms at glad.
2. Cheerful; willing: happy to help.
3. Characterized by good luck. See Synonyms at fortunate.
4. Being especially well-adapted; felicitous: a happy turn of phrase.
a. Characterized by a spontaneous or obsessive inclination to use something. Often used in combination: trigger-happy.
b. Enthusiastic about or involved with to a disproportionate degree. Often used in combination: money-happy; clothes-happy.
[Middle English, from hap, luck; see HAP.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2013 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The American Heritage Dictionary Blog
Check out our blog, updated regularly, for new words and revised definitions, interesting images from the 5th edition, discussions of usage, and more.
American Heritage Dictionary Products
The American Heritage Dictionary, 5th Edition
The American Heritage Dictionary of Idioms
The American Heritage Roget's Thesaurus
Curious George's Dictionary
The American Heritage Student Dictionary
The American Heritage Dictionary of Indo-European Roots
The American Heritage Student Grammar Dictionary
The American Heritage Desk Dictionary + Thesaurus
The American Heritage Science Dictionary
The American Heritage Dictionary of Business Terms
The American Heritage Children's Dictionary
The American Heritage Essential Student Thesaurus