All mouth and trousers means: Superficial, engaging in empty, boastful talk, but not of real substance.. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. If your teen uses it, context will usually make the intent clear. A short, curious question about where they heard it is usually all that is needed to know whether to follow up.
all mouth and trousers
(British, idiomatic) Superficial, engaging in empty, boastful talk, but not of real substance.
Definitions
UK
#1·Apr 27, 2026UK
(British, idiomatic) Superficial, engaging in empty, boastful talk, but not of real substance.
Origin: From mouth, meaning "talk" rather than action, and trousers, presumably at the time of origin, a reference to masculinity, either as trousers as a male item of clothing, or a reference to the genitals. Origin information sourced from Wiktionary contributors (CC BY-SA 4.0).
For parents
All mouth and trousers means: Superficial, engaging in empty, boastful talk, but not of real substance.. There is no real cause for parental concern; it is descriptive vocabulary rather than risky behaviour. If your teen uses it, context will usually make the intent clear. A short, curious question about where they heard it is usually all that is needed to know whether to follow up.
For ESL learners
all mouth and trousers means: Superficial, engaging in empty, boastful talk, but not of real substance.. Register: neutral, standard English. A common learner mistake is using the word in a register it does not fit, or assuming a single global meaning; native speakers immediately notice when slang appears in formal contexts, so always check the surrounding register before producing it yourself.
Cluster: dismissal
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For specific readers
Why is this section here?
Slang is read by different audiences for very different reasons. The For parents view re-explains the term in plain, non-judgemental language so a caregiver can understand what their child means without needing the surrounding subculture. The For English learners view focuses on register (when it's safe to use), formal alternatives, and common mistakes — what a textbook won't teach you.
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UK
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🇬🇧About British & Irish slang slang
UK and Irish slang — Cockney, Scouse, Geordie, Yorkshire, Glaswegian, Brummie, Welsh, West Country, plus Irish English. Centuries of regional dialects feeding into modern British and Irish street talk.
See all British & Irish slang slang on Slangora.
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Other words near "all mouth and trousers" (A)
all-in-one diaperall-in-two diaperall-IrelandAllisonall lives matterall mops and broomsall-nighterallocuteallocutionall of a doodahallophoneallosexual
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