off the deep end
Proposed by a contributor, not yet supported by evidence.
Meaning · English
to suddenly become completely involved or obsessed with something
Nghĩa · Tiếng Việt
bỗng dưng trở nên hoàn toàn tham gia hoặc ám ảnh
Machine-translated — suggest a fix
Literally: diving into the deep end of a pool
Where it’s used:
Used
Widespread English
Examples
Since Janet died, her husband has really gone off the deep end.Từ khi Janet chết, chồng của cô ấy thực sự trở nên chán nản.
Tatoeba sentence #836965 (CC BY 2.0 FR, tatoeba.org, retrieved 2026-07-31)
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 “off the deep end” mean?
to suddenly become completely involved or obsessed with something Literally: diving into the deep end of a pool
Is “off the deep end” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.