lessons learned

Proposed by a contributor, not yet supported by evidence.

Meaning · English

Knowledge or insights gained from experience, especially mistakes

Nghĩa · Tiếng Việt

kiến thức hoặc hiểu biết thu được từ kinh nghiệm, đặc biệt là từ sai lầm

Machine-translated — suggest a fix

Literally: learned lessons
Where it’s used: Used Widespread English

Examples

The team reviewed the project to document lessons learned

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 “lessons learned” mean?

Knowledge or insights gained from experience, especially mistakes Literally: learned lessons

Is “lessons learned” formal or informal?

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