bick ‧ er /ˈbɪkə $ -ər/ BrE AmE verb [intransitive]
[ Date: 1200-1300 ; Language: Middle Dutch ; Origin: bicken 'to attack' ]
to argue, especially about something very unimportant:
I wish you two would stop bickering.
bicker about/over
They kept bickering over who should answer the phone.
—bickering noun [uncountable]