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)
appearing dead; not breathing or having no perceptible pulse; "an inanimate body"; "pulseless and dead"
not breathing or able to breathe except with difficulty; "breathless at thought of what I had done"; "breathless from running"; "followed the match with breathless interest"
tending to cause suspension of regular breathing; "a breathless flight"; "breathtaking adventure"
a paste-up made by sticking together pieces of paper or photographs to form an artistic image; "he used his computer to make a collage of pictures superimposed on a map"
any collection of diverse things; "a collage of memories"