Black's Law Dictionary, Sixth Edition, p. 267:

comity.  Courtesy; complaisance; respect; a willingness to grant a privilege, not as a matter of right, but out of deference and good will.  Recognition that one sovereignty allows within its territory to the legislative, executive, or judicial act of another sovereignty, having due regard to rights of its own citizens.  Nowell v. Nowell, Tex.Civ.App., 408 S.W.2d 550, 553.  In general, principle of "comity" is that courts of one state or jurisdiction will give effect to laws and judicial decisions of another state or jurisdiction, not as a matter of obligation, but out of deference and mutual respect.  Brown v. Babbitt Ford, Inc., 117 Ariz. 192, 571 P.2d 689, 695.  See also Full faith and credit clause.

[Black's Law Dictionary, Sixth Edition, p. 267]