Reminisce

google

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early 19th century: back-formation from reminiscence.

wiktionary

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Back-formation from  reminiscence, from Latin reminīscēns, present participle of  reminīscor(“remember”). 

etymonline

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reminisce (v.)

1829, "to recollect," a back-formation from reminiscence. Meaning "indulge in reminiscences" is from 1871. "[S]omewhat colloquial" [OED] and mistrusted by the literary (in the OED's earliest citation for it, reminisce is followed immediately by an aside, "the word shall never enter my vocabulary"). Related: Reminisced. Reminiscing as a verbal noun, "action of remembering," is by 1891.