'rumor-related' originates from modern English compounding of the noun 'rumor' and the past-participial adjective 'related'. 'rumor' itself originates from Latin, specifically the word 'rumor' (acc. 'rumorem'), where the root 'rumor' meant 'noise, public talk'. 'related' comes from Latin, specifically the past participle 'relatus' of 'referre', where the prefix 're-' meant 'back' and 'ferre' (from 'tul-') meant 'to carry or bring'.

'rumor' changed from Latin 'rumor' to Old French 'rumour' and then to Middle English 'rumour', eventually becoming the Modern English 'rumor' (US)/'rumour' (UK). 'related' developed from Latin 'relatus' (past participle of 'referre') through Old French and Middle English forms of 'relate' and 'relaten', and eventually the past-participial adjective 'related' in Modern English. The compound 'rumor-related' is a modern concatenation of these two elements.

Initially, 'rumor' primarily meant 'noise' or 'public talk' and 'related' meant 'brought back' or 'narrated' (from the sense of reporting). Over time, 'rumor' kept the sense of unverified talk, and 'related' shifted to the general sense 'connected to'. Together in Modern English the compound means 'connected to or concerning rumors'.