The Spanish verb 'amigar' (to befriend) comes from the Latin verb 'amicare' meaning 'to make friendly.' 'Amicare' itself was derived from the Latin noun 'amicus' meaning 'friend.' The verb was adapted into Spanish with the standard -ar infinitive ending.

Several common Spanish words share this Latin root, including 'amigo' (friend), 'amigable' (friendly), and 'amistad' (friendship). All these words preserve the core meaning related to friendship and companionship from their Latin ancestor.

In English, we can find several words that come from the same Latin root 'amicus.' These include 'amicable' (friendly or peaceful), 'amiable' (friendly and pleasant), and 'amity' (friendly relations). The connection between the Spanish and English words is clear in both their meaning and form, as they all relate to friendship and positive relationships.