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mid-14c., of uncertain origin, perhaps meant to represent in sound the pulsation of arteries and veins or the heart. Related: Throbbed; throbbing. The noun is first attested 1570s.
v. throbbed, throb·bing, throbs
To beat rapidly or perceptibly, such as occurs in the heart or a constricted blood vessel. n.
A strong or rapid beat; a pulsation.