bird's mouth: meaning, definition, pronunciation and examples
Rare (Specialist/Technical)Technical / Professional
Quick answer
What does “bird's mouth” mean?
A notched joint cut into a piece of timber to allow it to rest securely on a horizontal surface, typically used in carpentry and roofing.
Audio
Pronunciation
Definition
Meaning and Definition
A notched joint cut into a piece of timber to allow it to rest securely on a horizontal surface, typically used in carpentry and roofing.
A specific carpentry and joinery technique for connecting structural members at right angles, resembling the open beak of a bird. It can also refer metaphorically to any small, sheltered nook or corner.
Dialectal Variation
British vs American Usage
Differences
Both varieties use the term identically within technical contexts (carpentry, roofing). No significant dialectal variation in meaning or form.
Connotations
Purely technical, neutral connotation. No regional emotional or stylistic differences.
Frequency
Equally rare/technical in both varieties. Slightly higher frequency in American English due to prevalence of DIY and timber-frame housing literature.
Grammar
How to Use “bird's mouth” in a Sentence
The rafter [VERB: has/cuts/fits into] a bird's mouth [PREP: on/over/onto] the wall plate.Vocabulary
Collocations
Examples
Examples of “bird's mouth” in a Sentence
verb
British English
- You need to carefully bird's-mouth the joist before fixing it to the beam.
American English
- First, bird's-mouth the rafter so it sits flush on the top plate.
adjective
British English
- The bird's-mouth joint provides excellent weight distribution.
American English
- Use a bird's-mouth cut for a stronger roof frame.
Usage
Meaning in Context
Business
Not used.
Academic
Used in architecture, engineering, and historical building conservation texts.
Everyday
Virtually never used in everyday conversation.
Technical
The primary context. Used in carpentry, roofing, timber framing, and boatbuilding manuals and on-site instructions.
Vocabulary
Synonyms of “bird's mouth”
Vocabulary
Antonyms of “bird's mouth”
Watch out
Common Mistakes When Using “bird's mouth”
- Writing it as "birds mouth" (missing apostrophe).
- Pronouncing it as "bird mouth" (dropping the /z/ sound).
- Using it in non-technical contexts where it would not be understood.
FAQ
Frequently Asked Questions
No, it is a specialist technical term used almost exclusively in carpentry, roofing, and related trades.
Yes, in professional jargon, it can be used verbally (e.g., 'to bird's-mouth a rafter'), though this is less common than its noun form.
A bird's mouth is a specific type of notch, usually cut at a right angle (often 90 degrees) to create a resting seat for a timber on another surface. Not all notches are bird's mouths.
The name comes from the visual resemblance of the cut-out notch to the wide-open beak of a bird, especially when viewed from the side.
A notched joint cut into a piece of timber to allow it to rest securely on a horizontal surface, typically used in carpentry and roofing.
Bird's mouth is usually technical / professional in register.
Bird's mouth: in British English it is pronounced /ˈbɜːdz maʊθ/, and in American English it is pronounced /ˈbɝːdz maʊθ/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “No common idioms exist for this technical term.”
Learning
Memory Aids
Mnemonic
Imagine a bird perched on a branch, its beak wide open and pointing down to grip the wood. The notch cut into the timber looks just like that open beak.
Conceptual Metaphor
TOOLS ARE BODY PARTS (a joint is a mouth).
Practice
Quiz
In which field is the term 'bird's mouth' primarily used?