the flattened weblike part of a feather consisting of a series of barbs on either side of the shaft | organ of locomotion and balance in fishes and some other aquatic animals |
mechanical device attached to an elevated structure; rotates freely to show the direction of the wind | a stabilizer on a ship that resembles the fin of a fish |
flat surface that rotates and pushes against air or water | one of a set of parallel slats in a door or window to admit air and reject rain |
a fin attached to the tail of an arrow, bomb or missile in order to stabilize or guide it | a shoe for swimming; the paddle-like front is an aid in swimming (especially underwater) |
| one of a pair of decorations projecting above the rear fenders of an automobile |
| the cardinal number that is the sum of four and one |