A spindle or axle of a wheel.
A stimulus or driving force.
A bar or beam of wood or iron, connecting the opposite wheels of a carriage, on the ends of which the wheels revolve.
A reel; a device around which thread, wire or cable is wound, especially a cylinder or spindle.
One of the rotating assemblies of a gas turbine engine, composed of one or more turbine stages, a shaft, and one or more compressor or fan stages.
A small swimming pool that can be used also as a spa.
A temporary storage area for electronic mail, etc.
To wind on a spool or spools.
To send files to a device or a program (a spooler or a daemon that puts them in a queue for processing at a later time).