The Spanish greeting 'hola' comes from a Latin expressive utterance. Like many greeting words across languages, it likely originated as a simple vocal expression used to get someone's attention or acknowledge their presence, rather than developing from a word with a more concrete meaning. Over time, this expression became standardized in Spanish as the common informal greeting we know today.

Since 'hola' itself is one of the first and simplest Spanish words that students learn, there aren't really any simpler related Spanish words to connect it to. It's a fundamental vocabulary word that stands on its own.

While 'hola' doesn't have any direct etymological relatives in English, it's worth noting that many greeting words across languages ('hello', 'hi', 'hey') similarly evolved from simple vocal expressions used to catch attention. This parallel development shows how different cultures often arrive at similar solutions for basic communication needs.