Etymology of tardy, retardation
Posted by Johannes on 22 December 2012
The adj. tardy comes from the Latin tardus (slow, dull, stupid), which most probably derives from the Greek vradys/vradus (slow; Gr: βραδύς; vradus/vardus/tardus].
Others etymologize it from the Latin taru-dos from the v. teru-, from the Greek terys/terus [thin, weak, wιthout power; Gr: τέρυς]
From the same root: tardiness, tardily, retard, retardation, brady- (bradycardia, bradypnea, bradykinesia etc).
In modern Greek:
a) vradys (bradys): slow [Gr: βραδύς]