co·a·lesce / ˌkōəˈles/ • v. [intr.] come together and form one mass or whole: the puddles had coalesced into shallow streams. ∎ [tr.] combine (elements) in a mass or whole: to help coalesce the community, they established an office.DERIVATIVES: co·a·les·cence / -ˈlesəns/ n.co·a·les·cent / -ˈlesənt/ adj.
So coalition XVII. — medL.