expatiate v.

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.).

c. 1300, "extent or area; room" (to do something), a shortening of Old French espace "period of time, distance, interval" (12c.), from Latin spatium "room, area, distance, stretch of time," a word of unknown origin (also source of Spanish espacio, Italian spazio).

From early 14c. as "a place," also "amount or extent of time." From mid-14c. as "distance, interval of space;" from late 14c. as "ground, land, territory; extension in three dimensions; distance between two or more points." From early 15c. as "size, bulk," also "an assigned position." Typographical sense is attested from 1670s (typewriter space-bar is from 1876, earlier space-key, 1860).

Astronomical sense of "stellar depths, immense emptiness between the worlds" is by 1723, perhaps as early as "Paradise Lost" (1667), common from 1890s. Space age is attested from 1946. Many compounds first appeared in science fiction and speculative writing, such as spaceship (1894, "A Journey in Other Worlds," John Jacob Astor); spacecraft (1928, Popular Science); space travel (1931); space station (1936, "Rockets Through Space"); spaceman (1942, Thrilling Wonder Stories). Space race attested from 1959. Space shuttle attested by 1970.

Space isn't remote at all. It's only an hour's drive away if your car could go straight upwards. [Sir Fred Hoyle, London Observer, 1979]

"act of expatiating," 1610s, noun of action from expatiate.