flare / fler/ • n. 1. a sudden brief burst of bright flame or light: the flare of the match lit up his face. ∎  a device producing a bright flame, used esp. as a signal or marker: a helicopter spotted a flare set off by the crew| [as adj.] a flare gun. ∎  [in sing.] a sudden burst of intense emotion: she felt a flare of anger within her. ∎  Astron. a sudden explosion in the chromosphere and corona of the sun or another star, resulting in an intense burst of radiation. See also solar flare. ∎  Photog. extraneous illumination on film caused by internal reflection in the camera.2. [in sing.] a gradual widening, esp. of a skirt or pants: as you knit, add a flare or curve a hem. ∎  an upward and outward curve of a vessel’s bow, designed to throw the water outward when under way.• v. [intr.] 1. burn with a sudden intensity: the blaze across the water flared the bonfire crackled and flared up. ∎  (of a light or a person's eyes) glow with a sudden intensity: her eyes flared at the stinging insult. ∎  (of an emotion) suddenly become manifest in a person or their expression: alarm flared in her eyes tempers flared. ∎  (flare up) (of an illness or chronic medical complaint) recur unexpectedly and cause further discomfort: Tracy's pain has flared up again, this time almost beyond enduring. ∎  (esp. of an argument, conflict, or trouble) suddenly become more violent or intense: in 1943 the Middle East crisis flared up again. ∎  (flare up) (of a person) suddenly become angry: she flared up, shouting at Jeff.2. [often as adj.] (flared) gradually become wider at one end: a flared skirt the dress flared out into huge a train. ∎  (of a person's nostrils) dilate: his head lifted, his nostrils flaring. ∎  [tr.] (of a person) cause (the nostrils) to dilate.

flare (flair) n.
1. reddening of the skin that spreads outwards from a focus of infection or irritation in the skin.

2. the red area surrounding an urticarial weal.

flare spread out, as hair, etc. XVI; burn with a spreading flame XVII. of unkn. orig.
Hence sb. XIX.