Frequently or many times; happening on a regular or recurring basis.
From 'often' (from Old English 'oft' meaning frequently) combined with 'times' (from Old English 'tīma'). It's a somewhat archaic construction that persists in formal or literary English.
Oftentimes is technically redundant—'often' already means multiple times—but we use it anyway, which shows how language loves reinforcement; we really want to EMPHASIZE that something happens a lot, so we layer the meanings!
Complete word intelligence in one call. Free tier — 50 lookups/day.