<jargon> Something (not a person) that loses; a situation in which something is losing. Emphatic forms include "moby loss", and "total loss", "complete loss". Common interjections are "What a loss!" and "What a moby loss!" Note that "moby loss" is OK even though **"moby loser" is not used; applied to an abstract noun, moby is simply a magnifier, whereas when applied to a person it implies substance and has positive connotations.
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Nearby terms: lose « loser « losing « loss » lossage » lossless » lossless audio compression