plumb
plumb
/plʌm/
(literary)
plumb something to try to understand or succeed in understanding something mysterious
She spent her life plumbing the mysteries of the human psyche.
He had clearly plumbed the general sense of the message.
Word Origin
verb Middle English (originally in the sense ‘sounding lead’): via Old French from Latin plumbum ‘lead’. plumb something in. late 19th cent.: back-formation from plumber.