The phrase "caught on to" is a common expression that means to understand or grasp something, or to become aware of something. Other synonyms for this phrase include "figured out", "got the hang of", "caught up with", "latched onto", "picked up on", "grasped", and "comprehended". These words are all commonly used to indicate understanding or awareness, but each has its own nuances and subtleties in meaning. By using a range of synonyms for "caught on to", speakers and writers can add variety and interest to their language and convey slightly different shades of meaning.