The Spanish word for bicycle is
bicicleta

Gender

The gender of bicicleta is feminine. E.g. la bicicleta.

The plural of bicicleta is bicicletas.

bicycle
1. n. Bicicleta

bicicleta
1. n-f. (exercise, vehicle) bicycle, pushbike, cycle
(coi, andar/montar en bicicleta, to ride a bike)
2. n-f. (soccer) step over, pedalada (a dribbling move, or feint, in football (soccer), used to fool a defensive player into thinking the offensive player, in possession of the ball, is going to move in a dir
3. n-f. (climbing) bicycle

bicicleta
1. nf. Vehículo, comúnmente de dos ruedas iguales, propulsado mediante la aplicación de la fuerza de las piernas sobre los pedales que la transmiten hacia los piñones y una cadena moviendo la rueda trasera.