a sudden burst of flame
"The campfire suddenly flared up when I dropped a handful of dry twigs onto the glowing embers."
reddening of the skin spreading outward from a focus of infection or irritation
"After the insect bite, his arm began to flare as redness spread rapidly away from the sting site."
a sudden recurrence or worsening of symptoms
"a colitis flare"
"infection can cause a lupus flare"
a sudden eruption of intense high-energy radiation from the sun's surface; associated with sunspots and radio interference
"The powerful solar flare disrupted our satellite communications for several hours before fading away."
am unwanted reflection in an optical system (or the fogging of an image that is caused by such a reflection)
"The bright streetlight created a distracting flare across the camera lens, washing out details in the night sky."
a sudden outburst of emotion
"she felt a flare of delight"
"she could not control her flare of rage"
a device that produces a bright light for warning or illumination or identification
"The sailor fired a red flare into the night sky to signal their distress to passing ships."
a short forward pass to a back who is running toward the sidelines
"he threw a flare to the fullback who was tackled for a loss"
(baseball) a fly ball hit a short distance into the outfield
"The batter managed to get a small flare on his first pitch before the catch was made in shallow right field."
A sudden bright light.
"The flare from the firework blinded everyone as it exploded in the night sky."
To cause to burn.
"The spark from his lighter managed to flare the dry leaves on the ground."