A testis is one of the two male sex organs that hang below the penis and make sperm. The everyday word in English is testicle; testis is the technical one, used in medicine, biology and science writing.

A testis is one of the two male sex organstestis是男性兩個生殖器官的其中一個， that hang below the penis垂在陰莖下方， and make sperm負責製造精子。 The everyday word in English is testicle英文日常用的字是testicle； testis is the technical onetestis則是專業用語， used in medicine, biology and science writing用在醫學、生物學和科學寫作裡。

If you are reading a biology textbook or a doctor's report you will see testis; if a friend is telling you about an injury, you will hear testicle, or one of many informal words.

If you are reading a biology textbook or a doctor's report如果你在讀生物課本或醫生的報告， you will see testis會看到testis； if a friend is telling you about an injury如果是朋友跟你講受傷的事， you will hear testicle, or one of many informal words你會聽到testicle，或其他許多口語的說法。

The plural is testes (say TEST-eez), not 'testises' — this is a Latin plural, like crisis → crises. In practice you meet the plural far more often than the singular, because there are normally two: 'the testes produce testosterone'.

The plural is testes複數是testes (say TEST-eez)（唸作TEST-eez）， not 'testises'不是「testises」—— this is a Latin plural這是拉丁文式的複數， like crisis → crises就像crisis變crises一樣。 In practice you meet the plural far more often than the singular實際上你遇到複數的機會遠比單數多， because there are normally two因為正常是兩個： 'the testes produce testosterone'「the testes produce testosterone（睪丸分泌睪固酮）」。

There is nothing rude about the word itself; it is the clean, neutral, professional term, which is exactly why it feels cold. A doctor in Taiwan writing in English would use it without hesitation.

There is nothing rude about the word itself這個字本身一點都不粗俗； it is the clean, neutral, professional term它是乾淨、中性、專業的用詞， which is exactly why it feels cold而這正是它讓人覺得冷冰冰的原因。 A doctor in Taiwan writing in English台灣的醫生用英文寫東西時， would use it without hesitation會毫不猶豫地用這個字。