bicker

From Middle English bikeren (“to attack”), from Middle Dutch bicken (“to stab, thrust, attack”) +‎ -er (frequentative suffix), from Old Dutch *bikken, from Proto-West Germanic *bikkjan, from Proto-Germanic *bikjaną, from Proto-Indo-European *bʰeg- (“to smash, break”).

See also Old English becca (“pickax”), Dutch bikken (“to hack”), German picken (“to peck, pick at”), Old Norse bikkja (“to plunge into water”); compare also German Low German bickern (“to nibble, gnaw”).

From Scots bicker, from Middle English biker. Doublet of beaker.