This is when a human is showing feelings to a special specimen
someone who does way too much for a person they like
Ali the simp : bro i made her assignments just to build trust, we are not even dating
dee : you're a simp
A white knight and Stan’s bastard child
simp: You are so perfect in every way. Please sleep with me my goddess
hoe: stfu simp
Strongly interacting massive particle (SIMP)
Simps are hypothetical particles that has since been discounted based on further observations and modelling of the cluster.