'decliners' originates from Modern English, formed from the verb 'decline' plus the agentive suffix '-er' (making 'decliner'), where the verb 'decline' ultimately comes from Latin 'declinare' (see below).

'decline' changed from Latin word 'declinare' into Old French 'decliner' and then into Middle English forms before becoming the modern English verb 'decline'; the noun 'decliner' was later formed by adding the suffix '-er', and 'decliners' is simply its plural.

Initially, the Latin root 'declinare' meant 'to bend or turn aside'; over time the sense broadened in English to include 'to refuse' and 'to slope or fall away', and the noun derived from it came to mean 'one who declines (an offer)'.