or half life, half·life
noun, plural half-lives [haf-lahyvz, hahf-] /ˈhæfˌlaɪvz, ˈhɑf-/.
Examples from the Web for half-life
The half-life of a piece of technology these days is very short.ecoATM offers consumers a new way to sell used cell phones and electronic devices|Sarah Langs|September 1, 2013|DAILY BEAST
But the half-life of a piece of hardware is very short these days.
And, finally, Moglaut had warned that the compact power unit pocketed on the left breast had a half-life of only thirteen years.Zero Data|Charles Saphro
By taking such an attitude to the past we should only fall into the half-will and half-life common to an age of decadence.Life's Basis and Life's Ideal|Rudolf Eucken
They amused themselves some time with these bright and beautiful creatures, which appear to have but a half-life.The Swiss Family Robinson; or Adventures in a Desert Island|Johann David Wyss
The half-life must find its mate or, after a few brief days, it dies, leaving its line extinct.Woman in Modern Society|Earl Barnes
She places herself as his equal—as the other half, without which his half-life cannot be complete.What a Young Husband Ought to Know|Sylvanus Stall
British Dictionary definitions for half-life
Medicine definitions for half-life
Science definitions for half-life
Culture definitions for half-life
In physics, a fixed time required for half the radioactive nuclei in a substance to decay. Half-lives of radioactive substances can range from fractions of a second to billions of years, and they are always the same for a given nucleus, regardless of temperature or other conditions. If an object contains a pound of a radioactive substance with a half-life of fifty years, at the end of that time there will be half a pound of the radioactive substance left undecayed in the object. After another fifty years, a quarter-pound will be left undecayed, and so on.