Chrismation or Confirmation is the sacrament in which the baptized receive the sealing and strengthening gift of the Holy Spirit.
Eastern and Western practice
Eastern churches ordinarily confer chrismation with holy chrism immediately after baptism, including upon infants. In much of the Western Church, confirmation is commonly administered later and often reserved to a bishop. In the United Roman-Ruthenian Church, chrismation is typically administered immediately following baptism, but may be administered separately later, particularly in the case of a persona already baptized. In the Roman-Ruthenian custom, chrismation is typically done by a bishop unless immediately following baptism performed by a priest.
Meaning
The sacrament completes baptismal initiation, strengthens the faithful for witness, and signifies full participation in the Spirit-filled life and mission of the Church.