The word "diss" is a slang word used primarily in the United States. It usually means that an insult or hurtful criticism has been spoken against another person. "Diss" is heavily used in hip hop music to convey the meaning of contempt in a more contained and lyrical fashion.
Many urban circles use the word "diss" to not only express criticism and contempt, but to indicate instances of ignoring or snubbing another person. When an individual ignores someone else's greetings or attempts to initiate a conversation, it is referred to as a "diss." In this case, the other person is publicly making it clear that contact is not welcome.
Reasons for "dissing" someone may vary. Some individuals may consider contact from people that they don't know to be intrusive. Others might not know how to react to certain types of communication and their soft responses or lack of appreciation may be interpreted as a "diss."
Open displays of disrespect may also be considered to be a "diss." If one person insults another with a rude remark about his personality, clothing or performance, it is considered to be "dissing." In some hip hop and rap lyrics, a "diss" might also indicate a public break-up of a romantic relationship.
Hurtful criticism that is meant to sting, make a strong impact, or discredit an individual can also fit the meaning of this slang word. When individuals attempt to take someone else down, lower his self-esteem or lower his public image, it causes others to perceive him negatively. The targeted individual is considered to be "dissed" since the other person feels the need to express his personal disapproval.
Attacks against someone else's character that point out certain flaws might be considered to be "dissing." Saying that another person isn't good at a certain task in an overtly negative fashion would also be an example of this. When someone is "dissed" by another person, the "disser" is publicly expressing disdain or strong dislike for the target's person or behavior.
Even a minor insult might be interpreted as someone "dissing" someone else. On the other hand, depending upon a person's sensitivity to criticism and insults, only blatant forms of disrespect and snubs might be considered to be a true "diss." Regardless, the experience of being "dissed" is not usually something positive or welcome.
Other forms of behavior that may be considered to be "dissing" include betraying someone in a personal relationship. Cheating on a romantic partner may be expressed as being "dissed." Many rap and hip hop lyrics refer to the act of cheating or ignoring romantic gestures as "dissing."