catch on to

1 to come to an awareness of she caught on to the fact that they were planning a surprise party Synonyms ascertain, discover (to), find out, get on (to), hear, learn, realize, see, wise (up)Related Words hit (on or upon), tumble (to); descry, detect, encounter, espy, see, spot; calculate, dope (out), figure out, find, puzzle (out); discern, mind, note, observe, perceive; divineNear Antonyms miss, overlook; disregard, ignore; forget, unlearn; blanket, blot out, cloak, conceal, cover, curtain, enshroud, hide, mask, occult, screen, shroud, veil

2 to have a clear idea of he finally caught on to the concept of phototaxis Synonyms appreciate, apprehend, assimilate, behold, catch, comprehend (to), cognize, compass, conceive, cotton (to or on to), decipher, decode, dig, discern, get, grasp, grok, intuit, know, make, make out, perceive, recognize, register, savvy, see, seize, sense, tumble (to), twig, understandRelated Words absorb, digest, take in; realize; fathom, penetrate, pierceNear Antonyms misapprehend, misconceive, misconstrue, misinterpret, misperceive, misread, mistake, misunderstandAntonyms miss