For Sale at Go Daddy:
There is one live trademark for Reefer's ("herbs for smoking") and one dead trademark for Reefers (clothing)
However, Reefer is a generic word, and Little Reefer is a brandable word, a possible name for a legal weed shop.
Given that Marijuana is still illegal in most states, consult with an attorney or expert for advice on how this term may be used in commerce.
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