SACRAMENT - an efficacious sign of grace, instituted by Christ and entrusted to the Church, by which divine life is given to us through the work do of the Holy Spirit.
GRACE - the free and undeserved gift that God gives us to respond to our vocation to become His adopted children. ACTUAL GRACE - God gives us the help to conform our lives to His will.
SANCTIFYING GRACE - God shares His divine life and friendship with us in a habitual gift, a stable and supernatural dispostion that enables the soul to live with God, to act by His love. Sanctifying grace heals our human nature wounded by sin, by giving us a share in the divine life of the Trinity.
SACRAMENTAL GRACE (and special graces, or charisms, the grace of one's state in life) are gifts of the Holy Spirit to help us live out our Christian vocation.
All definitions are from the Catechism of the Catholic Church