(n.) An apothecium in certain lichens, having a spherical surface marked with spiral or concentric ridges and furrows.
tricae
(pl. ) of Trica
tricarballylic
(a.) Of, pertaining to, or designating, a complex tribasic organic acid, C3H5.(CO2H)3 occurring naturally in unripe beet roots, and produced artificially from glycerin as a white crystalline substance.