pedal1
 
/
ˈpɛd(ə)l/
n.
    - each of a pair of foot-operated levers for powering a bicycle or other vehicle propelled by leg power.
- a foot-operated throttle, brake, or clutch control in a motor vehicle.
- each of a set of two or three foot-operated levers on a piano, for sustaining or softening the tone. ▸a foot-operated lever on other musical instruments, such as a harp or organ. ▸a foot-operated device for producing a sound effect on an electric guitar. 
- Music  short for pedal note.
v.
 (pedals, pedalling, pedalled; US pedals, pedaling, pedaled)
  - move by working the pedals of a bicycle.
- use the pedals of a piano, organ, etc.
Phrase
- with the pedal to the metal
 N. Amer. informal at full speed.
Derivative
Usage
People often confuse the words pedal and peddle. Pedal is a noun referring to a foot-operated lever, as on a bicycle, and a verb chiefly meaning ‘move by working the pedals of a bicycle’ (they pedalled along the road). Peddle, on the other hand, is a verb meaning ‘sell goods or promote an idea’ (he peddled printing materials around the country).
Etymology
C17: from Fr. pédale, from Ital. pedale, from L. pedalis (see pedal2).
pedal2
 
/
ˈpɛd(ə)l, 
ˈpiː-/
adj.
 chiefly Medicine  & 
Zoology  relating to the foot or feet.
Etymology
C17: from L. pedalis, from pes, ped- ‘foot’.