"an embrace (as of salutation) employed in Latin America." That doesn't do it justice either. The abrazo itself is just one of many forms of salutation common in this part of the world.
Between men, in most parts of Latin America, the abrazo is the most common of greetings. A handshake, followed by a mutual embrace and usually simultaneous firm pats on the back, and finishing up with a second handshake, is the most common style of abrazo. Women, children and older people, and men who are close or old friends, often will also exchange kisses on the cheek, and, sometimes, both cheeks.
Such greetings are exchanged upon first seeing someone, and upon bidding them farewell. In general, there is a much greater degree of physical intimacy in relationships in Latin America. Some parts of the region remain dominated by a pervasive culture of machismo, with men terrified of showing feelings, 'weakness' or intimacy. That is breaking down, however slowly.
In recent years in the United States, some men have begun mimicking the abrazo, but the effort more often than not consists of a second-rate and awkward back-slap -- something even NFL football players might do -- rather than a show of affection.
The casualness and intimate nature of each encounter, compared to the stiffness of the same salutation among Europeans or Americans, is another one of those undefined charms of life in the region. We can thank the Spanish and the Portuguese for all of it.