Definition one - "Slay" is a vocabulary used for killing someone, or something.
Definition two - "Slay" can be used for saying another word for "epic".
Definition three - "Slay" may be used for expressing your happiness.
But more importantly...
ðSLAYð¥°WHATðYOUðWANNAð âï¸SLAYðANDð¤©LETðTHEðSLAYðSLOUTð
^ That was a joke, IM SORRY-
"Oh my god! ðWeðslayð«FRð³"