a·lign / əˈlīn/ • v. 1. [tr.] place or arrange (things) in a straight line: brush the surface to align the fibers. ∎  put (things) into correct or appropriate relative positions: the fan blades are aligned | fig. aligning domestic prices with prices in world markets. ∎  [intr.] lie in a straight line, or in correct relative positions: the pattern of the border at the seam should align perfectly.2. (align oneself with) give support to (a person, organization, or cause): newspapers align themselves with certain political parties. ∎  [intr.] come together in agreement or alliance: all of them must align against the foe.

align XVII. — (O)F. aligner, f. phr. à ligne, repr. L. ad līneam in a straight line (see AD-, LINE2).
So alignment XVIII.