Someone asked me the other day how to sign "dairy."
There really isn't one specific sign for "dairy" that is widely recognized as meaning "dairy." The closest sign would be "MILK" or "MILK THINGS." If your conversation partner already understands the concept of "dairy" then you generally just fingerspell it (if you need to convey the specific term "dairy"). If for whatever reason you need to be more expansive in your reference to "dairy" (for example, suppose you are interpreting in a doctor's office and your client doesn't know what "dairy" means), you can spell D-A-I-R-Y and then follow that up by quickly signing "milk, cheese, yogurt, etc."
DAIRY = (MILK, CHEESE, YOGURT, ETC.)
MILK:
CHEESE:
YOGURT (YOGRT)
ETC.:
Notes: