Salary
Middle English: from Anglo-Norman French salarie, from Latin salarium, originally denoting a Roman soldier's allowance to buy salt, from sal ‘salt’.
wiktionary
From Middle English salarie, from Anglo-Norman salarie, from Old French salaire, from Latin salārium(“wages”), the neuter form of the adjective salārius(“related to salt”), from sal(“salt”). There have been various attempts to explain how the Latin term for “wages” came from the adjective “related to salt”. It is generally assumed that salārium was an abbreviation of salārium argentum(“salt money”), though that phrase is not attested. A commonly cited theory is that the phrase meant “money consisting of salt”, because Roman soldiers were sometimes paid in salt, but there is no evidence for this from ancient sources. Another is that the phrase meant “money used to buy salt [and other miscellaneous items]”. [1]
etymonline
salary (n.)
late 13c., "compensation, payment," whether periodical, for regular service or for a specific service; from Anglo-French salarie, Old French salaire "wages, pay, reward," from Latin salarium "an allowance, a stipend, a pension," said to be originally "salt-money, soldier's allowance for the purchase of salt" [Lewis & Short] noun use of neuter of adjective salarius "of or pertaining to salt; yearly revenue from the sale of salt;" as a noun, "a dealer in salt fish," from sal (genitive salis) "salt" (from PIE root *sal- "salt"). The Via Salaria was so called because the Sabines used it to fetch sea-salt near the Porta Collina. Japanese sarariman "male salaried worker," literally "salary-man," is from English.
salary (v.)
"to pay a regular salary to," late 15c., from salary (n.). Related: Salaried, which as an adjective in reference to positions originally was contrasted with honorary; lately with hourly.