A compound of head + bolt
Proto-Indo-European *kap- ‘head’
…
Proto-Germanic *haubudą ‘head’
Proto-West Germanic *haubud
Old English hēafod ‘head’
Middle English heed ‘head’
English head
Proto-Germanic *bultaz
Proto-West Germanic *bolt ‘bolt arrow’
Old English bolt
Middle English bolt
English bolt
Today it means
noun A bolt that is used to secure the head of something (such as the cylinder head of an internal combustion engine).
Language periods are conventional ranges, not dates for this word.
Etymograph / headbolt
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