What is another word for "fathom"?

Roget's Thesaurus (1911) lists these synonyms for "fathom": abysmal, acknowledge, acknowledgment, and, ankle, answer, antiphon, antiphony, bathometer, bathymetry, because, benthal, beyond, bottomless, cast, cause, clue, concavity, conclusive, counter, crater, deep, deepen, deepness, depression, depth, determine, dig, discover, discovery, draught, earth, echo, eureka, excavate, explain, explanation, fathomless, for, give.