Ful"crum (?), n.; pl. L. Fulcra (#), E. Fulcrums (#). [L., bedpost, fr. fulcire to prop.]

1. A prop or support.

2. (Mech.) That by which a lever is sustained, or about which it turns in lifting or moving a body.

3. (Bot.) An accessory organ such as a tendril, stipule, spine, and the like. [R.] Gray.

4. (Zoöl.) (a) The horny inferior surface of the lingua of certain insects. (b) One of the small, spiniform scales found on the front edge of the dorsal and caudal fins of many ganoid fishes.

5. (Anat.) The connective tissue supporting the framework of the retina of the eye.

• (mechanics): The pivot about which a lever turns.
  
• (military): NATO code name for the Soviet Mig 29 aircraft.