Roget’s II: The New Thesaurus, Third Edition. 1995.
apace
ADVERB:
In a rapid way: fast, posthaste, quick, quickly. Informal :flat out, hell-for-leather, lickety-split, pronto. Idioms: full tilt, in a flash, in nothing flat, like a bat out of hell, like a blue streak, like a flash, like a house on fire, like a shot, like a streak, like greased lightning, like the wind, like wildfire. SeeFAST.
