fan

Fan comes from Old English fann, meaning a winnowing basket, borrowed from Latin vannus, a tool for tossing grain into the wind so the husks blew away. That traces back to the Proto-Indo-European root *h₂weh₁-, meaning 'to blow.'

The word started as a farm tool for creating wind to clean grain, and its meaning of 'moving air' carried forward into the handheld and mechanical fans we know today. Separately, in US baseball slang, 'fan' also came to mean an enthusiast, as a clipping of 'fanatic,' possibly shaped by 'fancy' in the sense of a group of hobby enthusiasts.

It's a cousin of the Latin word ventus, meaning 'wind,' and of Dutch wan and German Wanne, both meaning 'winnowing basket' — all rooted in that same ancient idea of blowing air.