The Spanish word 'prota' is a colloquial shortening of 'protagonista', which comes from the Ancient Greek word 'πρῶτος' (protos), meaning 'first'. In modern Spanish slang, 'prota' has maintained this core meaning of being first or primary, specifically referring to the main character or protagonist of a story.

Some related Spanish words include 'protagonista' (protagonist), 'protocolo' (protocol), and 'prototipo' (prototype). All these words share the Greek root 'protos' meaning 'first' - a protagonist is the first or main character, a protocol is the first or primary set of rules, and a prototype is the first model of something.

English has many words derived from the same Greek root 'protos', including 'protagonist', 'protocol', 'prototype', and 'proton' (the first or primary particle in an atom). The prefix 'proto-' in English, meaning 'first' or 'original', comes from this same source, as in words like 'prototype' and 'protoplasm'.