1 [with object] place or arrange (things) in a straight line:the desks are aligned in straight rows facing forwards
put (things) into correct or appropriate relative positions:the fan blades are carefully aligned figurativealigning domestic prices with prices in world markets
[no object] lie in a straight line, or in correct relative positions:the pattern of the border at the joint should align perfectly
2 (align oneself with) give support to (a person, organization, or cause):newspapers usually align themselves with certain political parties
[no object] come together in agreement or alliance:all of them must now align against the foe
