Flak is defined as the bursting shells shot at aircraft from enemy guns on the ground, or criticism or opposition.
(noun)See flak in Webster's New World College Dictionary
noun
Origin: Ger < Fl(ieger)a(bwehr)k(anone), lit., flier defense gun
See flak in American Heritage Dictionary 4
also flack
nounOrigin:
Origin: German
Origin: , from Fl(ieger)a(bwehr)k(anone), aircraft-defense gun
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