The groin is the crease at the junction of the torso with the legs and the adjacent region that includes the external genitals. The term may be used as a euphemism for genitals, since the names of the latter are taboo words in some cultures. When someone has "pulled his/her groin muscles", usually, this person has pulled a muscle in the inner thigh.
The adjective inguinal refers to the groin region. There are a number of medical terms with this designation, including: