Fossil word

A fossil word is a word that is broadly but remains in currency because it is contained within an idiom still in use.

Fossil status can also occur for word senses and for phrases. An example for a word sense is 'navy' in 'merchant navy', which means 'commercial fleet' (although that sense of navy is obsolete elsewhere). An example for a phrase is '' (relevant), which is retained in the larger phrases '' (also 'case on point' in the legal context) and '', but is rarely used outside of a legal context.

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