Is it ensure, insure, or assure?
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 "salary, stipend, pension," originally "salt-money, soldier's allowance for the purchase of salt," noun use of neuter of adjective salarius "pertaining to salt," from sal (genitive salis) "salt" (see salt (n.)). Japanese sarariman "male salaried worker," literally "salary-man," is from English.
"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.