'shouter' originates from English, specifically the word 'shout' plus the agent-forming suffix '-er', where 'shout' is of imitative (echoic) origin representing a loud cry.

'shout' appeared in Middle English as forms like 'schouten'/'shouten' (likely imitative); the modern English 'shout' developed from these Middle English forms, and the agentive suffix '-er' was later added to create 'shouter'.

Initially, the root meant 'to utter a loud cry' (an onomatopoeic sense); over time it retained this core sense and 'shouter' came to mean 'a person who shouts' or one who calls out loudly.