Ling Ko is a Hindi word that refers to the male genitalia. It's a sensitive subject and requires a certain level of decorum when discussing it. There are several synonyms for Ling Ko, such as Shishna, Azoospermia, and Khandu. Some other commonly used synonyms include Loda, Zakar, and Guptang. These words are usually used in casual or vulgar conversations. However, medical professionals or people who work in the field of sex education usually use more clinical terms like Penis or Male sex organ. It's important to use respectful language while talking about body parts and to avoid using words that may cause offense.