ebullient adj.

word-forming element, in English meaning usually "out of, from," but also "upwards, completely, deprive of, without," and "former;" from Latin ex "out of, from within; from which time, since; according to; in regard to," from PIE *eghs "out" (source also of Gaulish ex-, Old Irish ess-, Old Church Slavonic izu, Russian iz). In some cases also from Greek cognate ex, ek. PIE *eghs had comparative form *eks-tero and superlative *eks-t(e)r-emo-. Often reduced to e- before -b-, -d-, -g-, consonantal -i-, -l-, -m-, -n-, -v- (as in elude, emerge, evaporate, etc.).

early 13c. (intransitive) "to bubble up, be in a state of ebullition," especially from heat, from Old French bolir "boil, bubble up, ferment, gush" (12c., Modern French bouillir), from Latin bullire "to bubble, seethe," from PIE *beu- "to swell" (see bull (n.2)). The native word is seethe. The figurative sense, of passions, feelings, etc., "be in an agitated state" is from 1640s.

I am impatient, and my blood boyls high. [Thomas Otway, "Alcibiades," 1675]

The transitive sense "put into a boiling condition, cause to boil" is from early 14c. The noun is from mid-15c. as "an act of boiling," 1813 as "state of boiling." Related: Boiled; boiling. Boiling point "temperature at which a liquid is converted into vapor" is recorded from 1773.

1749, from Latin ebullientem (nominative ebulliens) "a boiling, a bursting forth, overflow," present participle of ebullire "to boil over" (see ebullient). Related: Ebulliency (1670s), ebullition (c. 1400).