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