a·lign (?-l?n?)v. a·ligned, a·lign·ing, a·ligns v.tr.1. To arrange in a line or so as to be parallel: align the tops of a row of pictures; aligned the car with the curb.2. To adjust (parts of a mechanism, for example) to produce a proper relationship or orientation: aligning the wheels of a truck.3. To ally (oneself, for example) with one side of an argument or cause: aligned themselves with the free traders.v.intr.1. To adhere to a prescribed course of action. 2. To move or be adjusted into proper relationship or orientation.[French aligner, from Old French : a-, to (from Latin ad-; see ad-) + ligne, line (from Latin l?nea; see line1).]a·lign?er n.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.