half-second
UK[ˌhɑːf ˈsek.ənd]US[ˌhæf ˈsek.ənd]
n
A period of time lasting for half of one second; a very brief moment.
adj
Lasting for or relating to a period of half a second.
Morpheme Breakdown
half
second
half
partial
second
time unit
Etymology
The word 'half-second' is a transparent Modern English compound formed by combining two native elements. 'Half' originates from the Proto-Germanic halbaz, carrying the core sense of "partial" or "divided side," which evolved into the Old English 'healf' denoting one of two equal parts. 'Second' has a more circuitous journey, stemming from the Latin 'secundus' meaning "following" or "next in sequence," a sense preserved in terms like "second place." This temporal meaning was applied in medieval astronomy to the "second minute" (pars minuta secunda), a further subdivision of an hour, solidifying its role as a unit of time. The compound 'half-second' logically merges these concepts, using 'half' as a precise quantifier to specify a fraction of the established time unit 'second,' creating a term for an exceedingly brief but measurable duration.
Analysis
Structure: half (partial) + second (time unit)
half: From Old English 'healf', meaning "side, part," or "one of two equal parts." In this compound, it functions as a quantifier meaning "partial" or "fifty percent of."
second: From Old French 'secund', from Latin 'secundus' meaning "following, next," which came to denote the sixtieth part of a minute. In this compound, it functions as the base unit of time being modified.
Examples
The camera's shutter speed was set to a mere half-second.
There was a half-second delay before the sound reached the back of the hall.
In that critical half-second, the driver managed to swerve and avoid the collision.