"Hi-yas" is a colloquial expression that is often used as a greeting or a way to attract attention in informal settings. However, there are many synonyms for this word that can be used interchangeably depending on the context. Some common alternatives to "hi-yas" include "hey there," "hello," "greetings," "yo," "what's up," "hi," and "good to see you." Different cultures and regions may have their own unique greetings and salutations as well. Ultimately, the word you choose to use will depend on the situation and your personal preference.