on the sly : Dictionary / Wörterbuch (BEOLINGUS, TU Chemnitz)

English Dictionary: on the sly	by the DICT Development Group
2 results for on the sly
From WordNet (r) 3.0 (2006) [wn]:
on the sly adv in a furtive manner; "the soldiers were furtively crawling through the night" Synonym(s): furtively, on the sly
From Webster's Revised Unabridged Dictionary (1913) [web1913]:
Sly \Sly\, a. [Compar. {Slier}or {Slyer}; superl. {Sliest} or {Slyest}.] [OE. sli, slegh, sleih, Icel sl[?]gr, for sl[?]gr; akin to Sw. slug, Dan. slu, LG. slou, G. schlau; probably to E. slay, v.t.; cf. G. verschlagen sly. See {Slay}, v. t., and cf. {Sleight}.] 1. Dexterous in performing an action, so as to escape notice; nimble; skillful; cautious; shrewd; knowing; -- in a good sense. Be ye sly as serpents, and simple as doves. --Wyclif (Matt. x. 16). Whom graver age And long experience hath made wise and sly. --Fairfax. 2. Artfully cunning; secretly mischievous; wily. For my sly wiles and subtle craftiness, The litle of the kingdom I possess. --Spenser. 3. Done with, and marked by, artful and dexterous secrecy; subtle; as, a sly trick. Envy works in a sly and imperceptible manner. --I. Watts. 4. Light or delicate; slight; thin. [Obs.] {By the sly}, [or] {On the sly}, in a sly or secret manner. [Colloq.] [bd]Gazed on Hetty's charms by the sly.[b8] --G. Eliot. {Sly goose} (Zo[94]l.), the common sheldrake; -- so named from its craftiness. Syn: Cunning; crafty; subtile; wily. See {Cunning}.