For every nation We have ordained religious ceremonies [e.g. slaughtering of the beast of cattle during the three days of stay at Mina (Makkah) during the Hajj (pilgrimage)] which they must follow; so let them (pagans) not dispute with you on the matter (i.e. to eat of the cattle which you slaughter, and not to eat of cattle which Allah kills by its natural death), but invite them to your Lord. Verily! You (O Muhammad) indeed are on the (true) straight guidance. (i.e. the true religion of Islamic Monotheism).
Meaning:-
Slaughter: the killing or butchering of cattle, sheep, etc., especially for food.
Pagans: is a person who worships many gods or who worships nature and the Earth, a follower of a polytheistic
Monotheism: the doctrine or belief that there is only one God.