the act of being suspect or in question. doing something that is widely ill-advised and/or straight stupid. a sus person can be any one of the following - gay, a snitch, a trick, annoying, weird, retarted, stinky, thirsty, "the feds
", associated with the illuminati
, fat, short, old looking but actually young, a social loser, a tag along, a friend that you are ashamed of, a mexican, pretty much anything that has a derogatory meaning to it can be put under the sus category.