Ergi (noun) and argr (adjective) are two Old Norse terms of insult, denoting effeminacy or other unmanly behaviour. Argr is "unmanly" and ergi is "unmanliness"; the terms have cognates in other Germanic languages such as earh, earg, arag, or arug, among others.

Effeminacy or male femininity is the embodiment of feminine traits in boys or men, particularly those considered untypical of men or masculinity. These traits include roles, stereotypes, behaviors, and appearances that are socially associated with girls and women. Throughout history, men considered effeminate have faced prejudice and discrimination. Gay men are often stereotyped as being effeminate, and vice versa. However, femininity, masculinity, and other forms of gender expression are independent of sexual orientation.