incest
/ˈɪnsest/noun
mass noun
1- sexual relations between people classed as being too closely related to marry each other乱伦。
1.1
- the crime of having sexual intercourse with a parent, child, sibling, or grandchild乱伦罪。
词源
Middle English: from Latin incestus， incestum 'unchastity， incest'， from in- 'not' + castus 'chaste'.