“Minor orders” was a term used in the Church before the Second Vatican Council. Minor orders included various roles within the church such as tonsure, porter, lector, exorcist, and acolyte. Tonsure was the symbolic cutting of hair around the crown of the head. Monks and friars often had a large amount of their hair cut off with a single band of hair going horizontally across the back of their head. This was a sign of their consecrated life as religious. Diocesan clergy (parish priests), when tonsured, merely had a small amount of hair cut off from the back of the head, the usual place where many men get their so-called bald spot. Tonsure signified entrance into clerical life, but a man could still leave the seminary or monastery without needing to be dispensed by Rome should he discern he was not meant to go on further. Celibacy was not imposed during minor orders, only at subdiaconate.
Porter was the minor order in which a man was given the symbolic key; the term comes from medieval times—the porter was the guy who locked up at night and made sure visitors were allowed in while unfriendly elements stayed out. Lector was the next minor order, which authorized a man to recite the biblical readings at common prayer and at Mass. Exorcist was a minor order whereby a man could say prayers of exorcism during the rite of Baptism. He could not perform a formal exorcism ritual in the case of diabolical possession, though. Only a priest could do that, and only with permission of the local bishop. Acolyte was the minor order in which a man could light the altar candles, carry them in procession, and assist the deacon and subdeacon. Minor orders were replaced in 1972 with ministries of acolyte and lector. Candidacy replaced tonsure, and denotes that the man is officially studying for the priesthood and is attached to a diocese.