ebullient (adj.) Look up ebullient at Dictionary.com
1590s, "boiling," from Latin ebullientem (nominative ebulliens), present participle of ebullire "to boil over," literally or figuratively, from ex "out, out of" (see ex-) + bullire "to bubble" (see boil (v.)). Figurative sense of "enthusiastic" is first recorded 1660s.