'Rag dust' definitions:

Definition of 'Rag dust'

From: GCIDE

Rag \Rag\, n. [OE. ragge, probably of Scand, origin; cf. Icel. r["o]gg a tuft, shagginess, Sw. ragg rough hair. Cf. Rug, n.]
1. A piece of cloth torn off; a tattered piece of cloth; a shred; a tatter; a fragment. [1913 Webster]
Cowls, hoods, and habits, with their wearers, tossed, And fluttered into rags. --Milton. [1913 Webster]
Not having otherwise any rag of legality to cover the shame of their cruelty. --Fuller. [1913 Webster]
2. pl. Hence, mean or tattered attire; worn-out dress. [1913 Webster]
And virtue, though in rags, will keep me warm. --Dryden. [1913 Webster]
3. A shabby, beggarly fellow; a ragamuffin. [1913 Webster]
The other zealous rag is the compositor. --B. Jonson. [1913 Webster]
Upon the proclamation, they all came in, both tag and rag. --Spenser. [1913 Webster]
4. (Geol.) A coarse kind of rock, somewhat cellular in texture. [1913 Webster]
5. (Metal Working) A ragged edge. [1913 Webster]
6. A sail, or any piece of canvas. [Nautical Slang] [1913 Webster]
Our ship was a clipper with every rag set. --Lowell. [1913 Webster]
Rag bolt, an iron pin with barbs on its shank to retain it in place.
Rag carpet, a carpet of which the weft consists of narrow strips of cloth sewed together, end to end.
Rag dust, fine particles of ground-up rags, used in making papier-mach['e] and wall papers.
Rag wheel. (a) A chain wheel; a sprocket wheel. (b) A polishing wheel made of disks of cloth clamped together on a mandrel.
Rag wool, wool obtained by tearing woolen rags into fine bits, shoddy. [1913 Webster]