a group of interbreeding populations that is reproductively isolated from other such groups.

a category whose members are reproductively isolated from all other such groups

a group of individuals capable of interbreeding freely with one another but not with members of another species

a group of organisms that, in nature, are capable of interbreeding successfully with each other but that cannot interbreed with individuals outside the group

a population non-interbreeding in the case of animals (sterile progenies are produced even if they interbreed) but may be interbreeding in the case of plants

a population of similar individuals each of which is a representative of that species