Anointing with oil has all these meanings in the sacramental life. The pre-baptismal anointing with the oil of catechumens signifies cleansing and strengthening; the anointing of the sick expresses healing and comfort. The post-baptismal anointing with sacred chrism in Confirmation and ordination is the sign of consecration. By Confirmation Christians, that is, those who are anointed, share more completely in the mission of Jesus Christ and the fullness of the Holy Spirit with which he is filled, so that their lives may give off "the aroma of Christ."
Source: Catechism of the Catholic Church (Vatican.va)