- (by extension) Mental reach or scope; penetration; the extent of capacity; depth of thought or contrivance.
- (nautical) A measure of length corresponding to the outstretched arms, standardised to six feet, now used mainly for measuring depths in seas or oceans.
- (obsolete) Grasp, envelopment, control.
- (transitive, archaic) To encircle with outstretched arms, especially to take a measurement; to embrace.
- (transitive, figuratively) To get to the bottom of; to manage to comprehend (a problem etc.).
"I can't for the life of me fathom what this means."
- (transitive) To measure the depth of, take a sounding of.