grumbler

he is always a grumbler at work.

don't be such a grumbler; try to see the positive side.

she is known as the office grumbler.

grumblers often miss out on the fun.

the grumbler complained about the weather.

being a constant grumbler can affect your relationships.

my neighbor is a notorious grumbler.

grumblers can bring down the mood of a group.

sometimes, a grumbler just needs someone to listen.

it's hard to work with a habitual grumbler.