تعارفوا

They knew, or were acquainted with, one another. (S, O, K.)

And i. q. تَفَاخَرُوا [i. e. They vied, competed, or contended for superiority, in glorying, or boasting, or in glory, &c.; or simply they vied, one with another]: it occurs in a tradition, or, as some relate it, with ز; and both are explained as having this meaning. (TA.)