Third-person singular present tense of 'dredge'; to excavate and remove material from the bottom of a body of water, or to sift through something thoroughly.
From 'dredge', of unclear ultimate origin (possibly Dutch 'dregge'). The verb form gained specialized usage in maritime contexts from the 17th century onward.
The phrase 'dredge up' (meaning to unearth old memories or secrets) became common because dredges literally bring hidden things from deep water into the light—metaphor born from practical machinery.
Complete word intelligence in one call. Free tier — 50 lookups/day.