n.
      - a sudden brief burst of flame or light.
 - a device producing a very bright flame as a signal or marker.
 - a sudden burst of intense emotion.
 - Photography  extraneous illumination on film caused by internal reflection in the camera.
 - a gradual widening towards the hem of a garment. 
▸
(flares)
 trousers of which the legs widen from the knees down.
 - an upward and outward curve of a ship's bows.
 
v.
   - burn, shine, or be revealed with a sudden intensity.
 - 
(usu. flare up)
 suddenly become intense, angry, or violent.
 - gradually become wider at one end. 
▸(of the nostrils) dilate.
 
 
  Derivative
  
  Usage
  Do not confuse flare with flair: flare means ‘burn’ or ‘gradually become wider’, whereas flair means ‘a natural ability or talent’. Trousers may be flared, not flaired.
  Etymology
  C16 (in the sense ‘spread out one's hair’): of unknown origin.