As an example, the intromittent organ of most cephalopoda is the hectocotylus, a specialized arm, and male spiders use their pedipalps. The term penis applies to many intromittent organs, but not to all. Such organs occur in many animals, both vertebrate and invertebrate, but males do not bear a penis in every animal species, and in those species in which the male does bear a so-called penis, the penises in the various species are not necessarily homologous.
A penis (plural penises or penes ( /- n iː z/)) is the primary sexual organ that male animals use to inseminate females (or hermaphrodites) during copulation.
