In zoology, "monospecific" is an adjective describing a genus which contains only one known species. The term comes from the Greek prefix "μονο-" meaning "single" and Latin "species" meaning "kind" or "type". It is thus of hybrid origin.
Of the genera described in zoology, there are more monospecific genera than genera with any other individual number of species. Nevertheless, many genera originally considered monospecific, have been discovered to contain more than one species. Examples include Malapterurus the electric catfish and Loxodonta the African elephant. On the other hand, there are cases such as Pseudorinelepis where after an initial flurry of species descriptions a genus turns out to be monospecific.
In botany, "monotypic" or "unispecific" are used instead of "monospecificity" to refer to a taxon (at any rank) that includes only one species. "Monotypic" is also used in zoology, but with a different meaning.
In immunity, ""monospecific" refers to the operation of the immune system that B cell and T cell will only recognize a specific antigen and will not bind to another.