Meaning
Said of someone who fails to justify their wages - incompetent, lazy, or not delivering value for what they cost. Almost always used in the negative or in conditionals ('any plumber not worth their salt will check the pressure valve'); the underlying positive form, worth one's salt, means competent and deserving one's pay. Common, slightly informal. Informal and mildly critical; the positive 'worth one's salt' is now the more common form. Regional use: General English.
Origin
The stock story ties the idiom to Roman soldiers being paid in salt, via Latin salarium, the source of 'salary'. That derivation does not hold up: classicist Peter Gainsford finds no ancient evidence that soldiers were paid in, or given an allowance for, salt, and the 'salt money' gloss of salarium traces to eighteenth- and nineteenth-century Latin dictionaries rather than to antiquity; Pliny the Elder offers only a passing, speculative link between salt and official allowances. The English phrase itself is far later: the earliest known print citation is Philip Beaver's African Memoranda (1805), 'not worth his salt', and The Phrase Finder stresses that despite its ancient flavour the idiom is nineteenth-century English with no Roman lineage. The genuine basis is simply salt's long-standing value as a preservative and traded commodity, with 'salt' standing metonymically for one's keep or pay.
Research Sources
References used to check this entry’s meaning, history, or documented forms.
Variants
- not worth his salt
- worth one's salt
- worth their salt
- worth your salt
Usage Examples
- Any auditor not worth their salt would have flagged the duplicate invoices.
- The editor grumbled that the columnist was not worth his salt and replaced him within a month.
- If a safety inspector is worth their salt, they will cite the frayed wiring on sight.