Motion diagram. A Deaf-recorded clip from the PopSign corpus (CC BY 4.0) exists for this sign and can be placed here.
DIRTY
“dirty”
Hold an open hand under your chin, palm down, and wiggle the fingers.
Where the sign comes from
UnknownNo reliable source. We'd rather say so than invent one.
Its place and handshape are almost those of PIG, and the connection is often drawn. We have no source that confirms the sign was derived that way.
No sources — which is the point of the “unknown” tier. If you know of a documented account, the historical databases are where to check it.
The sign, taken apart
Every ASL sign is built from a handshape, a place it's made, and a movement. Learn to see these three and you can read and store any sign.
Made at the chin.
One-handed.
Repeated. Palm facing down.
Easy to confuse with
These differ from DIRTY in one or two parameters — the minimal pairs our receptive drills use to make sure you can really tell them apart.