catch, capture
捉 centers on seizing or taking hold of something: catching or capturing a person, animal, or idea.
捉 combines 扌 (hand) with 足 (foot), suggesting catching or capturing with the hands and feet. The exact historical development is uncertain, but the component combination is consistent with the meaning.
A hand 扌 and a foot 足 work together to catch something: you grab with your hand and chase with your feet to capture it.
For ソク, imagine catching a sock that is slipping off your foot: sock -> ソク, and your hand grabs it before it falls.
to catch; to capture; to seize; to arrest; to grab; to catch hold of
capture; seizure; prehension; trapping
key to understanding; point (e.g. of an argument)
to impress; to charm
to grasp the meaning
grasping (a meaning)
hard to figure out; elusive; slippery; vague; subtle
interpretation; perception; understanding
scavenger
trying to reach above one's station and failing; trying to accomplish something beyond one's abilities and failing; monkey catching (a reflection of) the moon (in the water)
to pounce on someone's words; to cavil at someone's words; to trip someone up with their own words