Penis is an external genital organ of male of some of the vertebrate and invertebrate both. शिश्न (Penis) कशेरुकी और अकशेरुकी दोनो प्रकार के कुछ नर जीवों का एक बाह्य यौन अंग है।
परिभाषा
any animal lacking a backbone or notochord; the term is not used as a scientific classification
lacking a backbone or spinal column; "worms are an example of invertebrate animals" पर्याय: spineless,
मोबाइल