from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun A small, specialized club-shaped structure typically bearing four basidiospores at the tips of minute projections. The basidium is unique to basidiomycetes and distinguishes them from other kinds of fungi.
from The Century Dictionary.
- noun In botany, an enlarged cell in basidiomycetous fungi, arising from the hymenium, and producing by abstriction spores borne upon slender projections at its summit.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Bot.) A special oblong or pyriform cell, with slender branches, which bears the spores in that division of fungi called
Basidiomycetes, of which the common mushroom is an example.
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun mycology A small structure, shaped like a
club, found in the Basidiomycotadivision of fungi, that bears four sporesat the tips of small projections.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun a small club-shaped structure typically bearing four basidiospores at the ends of minute projections; unique to basidiomycetes
from The American Heritage® Dictionary of the English Language, 4th Edition
Jamie's blunt forefinger flipped one off its stem, and traced the spokes of the basidium as he marshaled his next words.
At the apex of each basidium a flask-shaped cell, "sterigma" (d), appears.
In _F_, a basidium is shown, with the young spores just forming.
Each cell of the spore sends out a tube (Fig. 47, _C_), through an opening in the outer wall, and this tube rapidly elongates, the spore contents passing into it, until a short filament (basidium) is formed, which then divides into several short cells.
All of the group are characterized by the production of spores at the top of special cells known as basidia,  the number produced upon a single basidium varying from a single one to several.
From each one of these cells of the basidium a long, slender process (sterigma) grows out to the surface of the plant and bears the spore.
Ingold CT (1992) The basidium: a spore gun of precise range.
(usually four) little points, at the end of which spores are formed in exactly the same way as we saw in the germinating teleuto spores of the cedar rust, all the protoplasm of the basidium passing into the growing spores (Fig. 48, _E_, _F_).
_tr_ = = trama; _sh_ = = sub-hymenium; _b_ = = basidium, the basidia make up the hymenium; _st_ = = sterigma; _g_ = = spore.