half-life
— Noun
– English
～ the time required for something to fall to half its initial value (in particular, the time for half the atoms in a radioactive substance to disintegrate)
half life
— Noun
– English
～ the time required for something to fall to half its initial value (in particular, the time for half the atoms in a radioactive substance to disintegrate)
heavy lifting
— Noun
– English
～ difficult work; "the boss hoped the plan would succeed but he wasn't willing to do the heavy lifting"
half-light
— Noun
– English
～ a greyish light (as at dawn or dusk or in dim interiors)
heat lightning
— Noun
– English
～ bright flashes of light near the horizon without thunder (especially on hot evenings); usually attributed to distant lightning that is reflected by clouds