Pax \Pax\, n. Friendship, or a friend; -- esp. in the phrases to make pax with, to make friends with, to be good pax, to be good friends; also, truce; -- used esp. interjectionally. [Eng. Schoolboy Slang]

Source: Webster's Revised Unabridged Dictionary (1913)
 

Pax \Pax\, n. [L. pax peace. See Peace.]

1. (Eccl.) The kiss of peace; also, the embrace in the sanctuary now substituted for it at High Mass in Roman Catholic churches.

2. (R. C. Ch.) A tablet or board, on which is a representation of Christ, of the Virgin Mary, or of some saint and which, in the Mass, was kissed by the priest and then by the people, in medi[ae]val times; an osculatory. It is still used in communities, confraternities, etc.

Kiss the pax, and be quiet like your neighbors. --Chapman.

Source: Webster's Revised Unabridged Dictionary (1913)