A person who delves; someone who digs or investigates thoroughly and carefully.
From 'delve' (verb) + '-er' (agent suffix). The '-er' suffix attaches to verbs to name someone who performs the action. 'Delver' has been used since Middle English, though it's not extremely common today.
English lets us build 'delver,' 'digger,' 'explorer,' and 'investigator'—slightly different flavors of the same action. 'Delver' sounds more scholarly and deliberate than 'digger.'
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