Liturgy can refer to the Holy Sacrifice of the Mass, but it is a broader term. It refers to any official liturgy of the Church. The Divine Office can be celebrated solemnly as a liturgy.
This is a good general explanation. If the priest were focusing specifically on the Mass, I would suggest that the sacrificial aspect be included in the understanding of the so-called "Eucharistic Liturgy" which I admit is a bland term:
A new video is offered on Youtube on Sunday evening at this site: www.elementsofthecatholicmass.com.