moss

puffs of dirt and dust. How long has it been since you swept under this bed? There's a mountain of curly dirt under here! No one's been in this room for an age. Look at all the cobwebs and curly dirt. She was a terrible housekeeper. House moss collected in all the corners of her rooms.

Prov. A person who does not settle down is not attached to anything or anyone. (Can be said in admiration or in censure, depending on whether or not the speaker feels it is good to be attached to something or someone.) I worry about Tom. He's never lived in the same place for two years in a row, and he keeps changing jobs. A rolling stone gathers no moss.

A person who moves about a great deal and never settles down, as in Kate's lived in ten cities in as many years-she's a real rolling stone. This expression is a shortening of the proverb a rolling stone gathers no moss, first recorded in 1523, which indicates that one who never settles anywhere will not do well. After some 300 years of this interpretation, in the mid-1800s the value of gathering moss (and staying put) began to be questioned, and in current usage the term is most often used without any particular value judgment.