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Having or designating floral whorls with equal numbers of parts in each whorl.


1. (Biology) having an equal number of parts or markings
2. (Botany) (of flowers) having floral whorls with the same number of parts. Compare anisomerous


(aɪˈsɒm ər əs)

1. having an equal number of parts, markings, etc.
2. (of a flower) having the same number of members in each whorl.
References in periodicals archive ?
Flowers unisexual or bisexual, 4-5-6-merous, bracteates or not; epicalyx entirely in the form of a sheath; androecium isomerous, stamens epipetalous, stigma and style undivided.
Minor monosymmetry is also present in flowers in which the floral whorls are not isomerous (or asymmetric if the symmetry plane is oblique).
Delimitation is commonly not problematic, because calyx and corolla both occur in an isomerous whorl or series of sepals and petals.