mimmering

Uncertain. Possibly an alteration of mammering; or a derivation from earlier unrecorded *mimmer, from Middle Dutch mimmeren, mīmeren ("to ponder"; > Modern Dutch mijmeren (“to ponder, muse”)); or perhaps representing a continuation of Old English mymerian, mimorian (“to remember, commemorate”). See also mammer, mimmerkin.

来源：wiktionary