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Definition of hex key
hex key
Plural:hex keys
hex key Lexical Profile
CEFR
B2
Grade
6
Tier
2
Usage
Top 10k
• noun
1
A small, typically L-shaped hand tool used for driving bolts or screws that have a hexagonal socket in their heads.
Example
"You will need a four-millimeter hex key to securely assemble the wooden frame of the bed."
Synonyms
View all synonyms for hex keyWord Nuance & Usage
In many English-speaking regions, a hex key is most commonly referred to by the proprietary eponym 'Allen wrench' (chiefly North American) or 'Allen key' (chiefly British and Commonwealth).
Word Origin & Etymology
A compound of 'hex' (clipped from 'hexagonal', from Greek 'hex' meaning 'six') and 'key'. The tool was popularized in the early 20th century by various manufacturers, most notably the Allen Manufacturing Company in 1910.
Cite this Entry
Wordmom. (2026). Definition of Hex key. In Wordmom Dictionary. Retrieved Oct 14, 2026, from https://wordmom.com/dictionary/hex key