on the sly

Proposed by a contributor, not yet supported by evidence.

Meaning · English

Secretly or stealthily, often to avoid detection

Nghĩa · Tiếng Việt

Bí mật hoặc lén lút

Machine-translated — suggest a fix

Literally: on the sly
Where it’s used: Used Widespread English

Examples

She ate the cake on the sly, so no one would know

AI-drafted example auto-approved by rule (illustrative, not a corpus attestation)

Sources & notes

Listed in Wiktionary’s “English idioms” category (retrieved 2026-07-29); definition pending editorial review. Definition drafted by AI (@cf/meta/llama-3.3-70b-instruct-fp8-fast) and auto-approved by rule on 2026-07-31; pending editor spot-check.

Common questions

What does “on the sly” mean?

Secretly or stealthily, often to avoid detection Literally: on the sly

Is “on the sly” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.