From a dialectal variant of fumble.
From Middle Dutch femele, fimele (“cannabis brevior”), from fimelen ("to tease: flax, hemp, wool, etc."; also, "to move quickly, fiddle, play, trifle"; > Dutch fijmelen, femelen), related to Middle Low German fimmelen, fimmeren (“to grope about”), German fimmeln (“to grope; fumble”), West Frisian fimelje (“to pick; fiddle' trifle”), English fimble (“to fumble”).
fimble (plural fimbles)
- the male hemp plant