@panpannn Simp (/ sɪmp / ⓘ) is an internet slang term describing someone who shows excessive sympathy and attention toward another person, typically someone who does not reciprocate the same feelings, in pursuit of affection or a sexual relationship.
There you go, now you have the definition of simp. It used to mean men that did stupid things like pay a womens monthly car payment hoping that it would lead to a relationship, but now every idiot says it to anyone that does or says anything to someone else.