• Webster's Revised Unabridged Dictionary
    • Trimorphism (Biol) The coëxistence among individuals of the same species of three distinct forms, not connected, as a rule, by intermediate gradations; the condition among individuals of the same species of having three different shapes or proportions of corresponding parts; -- contrasted with polymorphism, and dimorphism.
    • Trimorphism (Crystallog) The property of crystallizing in three forms fundamentally distinct, as is the case with titanium dioxide, which crystallizes in the forms of rutile octahedrite, and brookite. See Pleomorphism.
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Century Dictionary and Cyclopedia
    • n trimorphism In crystallography, the property of crystallizing in three fundamentally different forms. Titanium dioxid, TiO2, is an example of trimorphism. In one form it is the mineral octahedrite or anatase; in another, rutile; in a third, brookite.
    • n trimorphism In biology, existence under three distinct forms. It is not rare among insects.
    • n trimorphism In botany, the occurrence of three distinct forms of flowers or other parts upon the same plant, or upon plants of the same species. In trimorphous flowers there are three sets of stamens and pistils, which may be called respectively long, middle, and short-length, and in which the pollen from the long stamens is capable of fertilizing only the long-styled forms, the mid-length stamens the mid-styled, etc. Compare dimorphism, and see heterogonaus trimorphism, under heterogonous.
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Chambers's Twentieth Century Dictionary
    • n Trimorphism trī-mor′fizm (biol.) the existence of an organism in three distinct forms, as in certain butterflies, in the common flower Lythrum salicaria, &c
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Webster's Revised Unabridged Dictionary
See Trimorphic


In literature:

There are, also, cases of dimorphism and trimorphism, both with animals and plants.
"On the Origin of Species" by Charles Darwin
Publishes papers on dimorphic and trimorphic plants.
"The Life and Letters of Charles Darwin, Volume II (of II)" by Charles Darwin
All dimorphic and trimorphic plants present such difference in function and in size.
"More Letters of Charles Darwin Volume II" by Charles Darwin
On the character and hybrid-like nature of the offspring from the illegitimate unions of dimorphic and trimorphic plants.
"Life of Charles Darwin" by G. T. (George Thomas) Bettany
TRIMORPHIC plants, conditions of reproduction in, ii.
"The Variation of Animals and Plants Under Domestication, Volume II (of 2)" by Charles Darwin
Hexachlorethane is trimorphous, forming rhombic, triclinic and cubic crystals; the successive changes occur at about 44 deg.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1" by Various
Dimorphism and trimorphism in plants, papers on, 45.
"Charles Darwin: His Life in an Autobiographical Chapter, and in a Selected Series of His Published Letters" by Charles Darwin