Wave offering refers to a sacrificial method where the priest lifts and waves the offering up and down.
{{:Old Testament Sacrificial Methods}}
Lev 7:29“Speak to the people of Israel and say to them: ‘Anyone who brings a fellowship offering to the Lord must bring part of it as their personal offering to the Lord.Lev 7:30With their own hands they are to bring the food offerings presented to the Lord: the fat together with the breast. The priest is to wave the breast before the Lord as a wave offering.Lev 7:31The priest shall burn the fat on the altar, but the breast belongs to Aaron and his sons.