“These three parts [of the Sacrament of Penance], then, are so intimately connected with one another, that
contrition includes the intention and resolution of
confessing and making
satisfaction; contrition and the resolution of making satisfaction imply confession; while the other two precede satisfaction.” - The Catechism of the Council of Trent
Source:
cin.org/users/james/ebooks/master/trent/tsacr-p.htm
Penance is made up of contrition, confession, and satisfaction. Satisfaction is just one part of penance.
The same Catechism defines the meaning of the word, penance, as such:
"Interior penance consists in turning to God sincerely and from heart, and in hating and detesting our past transgressions, with a firm resolution of amendment of life, hoping to obtain pardon through the mercy. Accompanying this penance, like inseparable companion of detestation for sin, is a sorrow and sadness, which is a certain agitation and disturbance of the soul, and is called by many a passion. Hence many of the Fathers define penance as an anguish of soul.
“Penance, however, in those who repent, must be preceded by faith, for without faith no man can turn to God. Faith, therefore, cannot on any account be called a part of penance.”