'Buddhist-related' originates from Modern English, specifically the words 'Buddhist' and 'related', where 'Buddhist' ultimately derives from Sanskrit 'buddha' meaning 'awakened one' plus the agent suffix '-ist', and 'related' comes from Latin 'relatus' (from 'referre') where 're-' meant 'back' and 'ferre' meant 'to carry'.

'Buddhist' changed from Sanskrit 'buddha' (adopted into Pali and later into European languages) and entered English as 'Buddha' and then 'Buddhist'; 'related' changed from Latin 'relatus' through Old French 'relater' and Middle English 'relaten' and eventually became the modern English word 'related'.

Initially, 'Buddhist' referred specifically to followers or things of the Buddha and 'related' originally had senses tied to 'carrying back' or reporting; over time their compound use evolved to the straightforward modern meaning of 'connected to Buddhism'.