Which prefix means all?

ante-
ante -

aero-
aero -

pro-
pro -

omni-

omni-

The prefix that means "all" is "omni-".

The prefix "omni-" means "all." If you come across a word with the prefix "omni-," you can assume it is related to the concept of "all" or "every." For example, "omniscient" means having all knowledge, "omnipotent" means having all power, and "omnivorous" means eating all types of food. Remembering these examples can help you understand the meaning of other words with the "omni-" prefix.