FURTIVELY

furtively, on the sly

(adverb) in a furtive manner; “the soldiers were furtively crawling through the night”

Source: WordNet® 3.1

Etymology

Adverb

furtively (comparative more furtively, superlative most furtively)

In a furtive manner.

Synonyms

• secretively

• surreptitiously

Source: Wiktionary

Fur"tive*ly, adv.

Definition: Stealthily by theft. Lover.

FURTIVE

Fur"tive, a. Etym: [L. furtivus, fr. furtum theft, fr. fur thief, akin to ferre to bear: cf. F. furtif. See Fertile.]

Definition: Stolen; obtained or characterized by stealth; sly; secret; stealthy; as, a furtive look. Prior. A hasty and furtive ceremony. Hallam.

Source: Webster’s Unabridged Dictionary 1913 Edition