Gone out of use; no longer in use: as, an obsolete word; an obsolete custom; an obsolete law. Abbreviated obsoleteIn descriptive zoöl., indistinct; not clearly or sharply marked; applied to colors, faded, dim: as, an obsolete purple; applied to ornaments or organs, very imperfectly developed, hardly perceptible: as, obsolete striæ, spines, ocelli.To become obsolete; pass out of use.To make obsolete; render disused.In botany, notingan organ which is rudimentary or scarcely apparent.