filler cap: meaning, definition, pronunciation and examples
Low-MediumNeutral / Technical
Quick answer
What does “filler cap” mean?
The removable or screw-on cover for the opening of a vehicle's fuel tank.
Audio
Pronunciation
Definition
Meaning and Definition
The removable or screw-on cover for the opening of a vehicle's fuel tank.
A cover for an opening, typically a fuel or fluid reservoir, designed to seal it.
Dialectal Variation
British vs American Usage
Differences
In British English, 'filler cap' is standard. In American English, 'gas cap' or 'fuel cap' is more common.
Connotations
Neutral technical term; no strong regional connotations beyond lexical preference.
Frequency
More frequent in British English; in AmE, 'gas cap' dominates.
Grammar
How to Use “filler cap” in a Sentence
the [ADJ] filler capremove the filler cap[VERB] the filler cap on/offVocabulary
Collocations
Examples
Examples of “filler cap” in a Sentence
verb
British English
- [none]
American English
- [none]
adverb
British English
- [none]
American English
- [none]
adjective
British English
- [none]
American English
- [none]
Usage
Meaning in Context
Business
Rare; only in automotive retail or manufacturing.
Academic
Rare; only in engineering or design papers.
Everyday
Used when discussing vehicle maintenance or refuelling.
Technical
Standard term in automotive manuals and engineering.
Vocabulary
Synonyms of “filler cap”
Strong
Neutral
Weak
Vocabulary
Antonyms of “filler cap”
Watch out
Common Mistakes When Using “filler cap”
- Misspelling as 'filler cab' or 'filler cup'.
- Using 'filler cap' for a radiator or oil cap (specificity error).
FAQ
Frequently Asked Questions
Rarely. It can refer to caps on other fuel tanks (e.g., boats, generators) but is overwhelmingly automotive.
Yes, 'petrol cap' is a common, slightly less formal synonym in BrE.
It can be illegal, may cause fuel spillage, trigger a check-engine light, and allows debris into the tank.
It is a two-word compound noun, often hyphenated (filler-cap) when used attributively (e.g., 'filler-cap design').
The removable or screw-on cover for the opening of a vehicle's fuel tank.
Filler cap is usually neutral / technical in register.
Filler cap: in British English it is pronounced /ˈfɪlə ˌkap/, and in American English it is pronounced /ˈfɪlɚ ˌkæp/. Tap the audio buttons above to hear it.
Phrases
Idioms & Phrases
- “[none]”
Learning
Memory Aids
Mnemonic
Think: You FILL the tank, then CAP it.
Conceptual Metaphor
A SEAL (for a container of energy/liquid).
Practice
Quiz
What is the most common American English equivalent for 'filler cap'?