Ally Al*ly", v. t. [imp. & p. p. {Allied}; p. pr. & vb. n. {Allying}.] [OE. alien, OF. alier, F. alier, fr. L. alligare to bind to; ad + ligare to bind. Cf. {Alligate}, {Alloy}, {Allay}, {Ligament}.] 1. To unite, or form a connection between, as between families by marriage, or between princes and states by treaty, league, or confederacy; -- often followed by to or with. [1913 Webster]

O chief! in blood, and now in arms allied. --Pope. [1913 Webster]

2. To connect or form a relation between by similitude, resemblance, friendship, or love. [1913 Webster]

These three did love each other dearly well, And with so firm affection were allied. --Spenser. [1913 Webster]

The virtue nearest to our vice allied. --Pope. [1913 Webster]

Note: Ally is generally used in the passive form or reflexively. [1913 Webster]

The Collaborative International Dictionary of English. 2000.