Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

English definition of “sly”

See all translations

sly

adjective uk   /slaɪ/ (slyer, slyest) us  
deceiving people in a clever way in order to get what you want: He's a sly old devil - I wouldn't trust him with my money. [before noun] seeming to know secrets: "You'll find out eventually," said Mary with a sly smile.
slyly
adverb uk   /ˈslaɪ.li/ us  
She grinned slyly and refused to tell me where the money came from.
slyness
noun [U] uk   /ˈslaɪ.nəs/ us  

sly

noun uk   /slaɪ/ us  
on the sly If you do something on the sly, you do it secretly because you should not be doing it: He drives his mother's car on the sly while she's at work.
(Definition of sly from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of sly?
Add Cambridge dictionaries to your browser to your website

“sly” in English

More meanings of “sly”

Definitions of “sly” in other dictionaries

Word of the Day

lamb

a young sheep, or the flesh of a young sheep eaten as meat

Word of the Day

The way we move (Verbs for walking and running)

by Kate Woodford,
March 25, 2015
​​​ This week we’re looking at interesting ways to describe the way that people move. Most of the verbs that we’ll be considering describe how fast or slow people move. Others describe the attitude or state of mind of the person walking or running. Some describe both. Starting with verbs for walking slowly,

Read More 

stackin’ p

March 30, 2015
idiom slang earning a lot of money ‘That’s a very generous present.”Yeah, well, she’s stackin’ p, innit?’

Read More