Main Entry: in·mate
Pronunciation: 'in-"mAt
Function: noun
Date: 1589
: any of a group occupying a single place of residence; especially : a person confined (as in a prison or hospital)
If no one thinks it's insulting but you, then you're too sensitive.
You're showing your ignorance on this. I'm not going to bother explaining it to you because you wouldn't understand.
Not everthing can be found in the dictionary or encyclopedia.