Reflex is defined as something that you do or think automatically, or a reflection.(noun)
When something is flying at your head and you instinctively close your eyes without thinking about it, this is an example of a reflex.
The definition of reflex is something done automatically without thinking about it, or something reflected back.(adjective)
Hiccuping is an example of something that would be described as a reflex action.
See reflex in Webster's New World College Dictionary
Origin: < L reflexus, reflected, pp. of reflectere: see reflect
See reflex in American Heritage Dictionary 4
Origin: From Middle English reflexen, to refract light, bend back
Origin: , from Latin reflexus
Origin: , past participle of reflectere, to bend back; see reflect.
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