Definition of "apothecium" []

• A disk-shaped or cup-shaped ascocarp of some lichens and the fungi Ascomycetes. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Nylander called the apothecium pale within, but forms with red-brown hypothecia are admitted by later writers."
• "A portion of a section through an apothecium of _Peltigera canina_, showing part of the hymenium of interwoven hyphae below and the bases of three paraphyses above."
• "A vertical section through an apothecium of _Lecidea rupestris_: a, the hymenium, composed of asci and paraphyses; b, the hypothecium; c, the mycelium, the cells of the algal host, and particles of the limestone on which the plant was growing; d, the weak, light-colored, covered exciple."