The Oxford Thesaurus An A-Z Dictionary of Synonyms - additionn.

1) adding, joining, putting together, uniting, combining: The addition of this paragraph is uncalled for. 2) totalling, adding up, summing-up, summation, counting up, reckoning, totting up: You have made an error in addition. 3) addendum, appendix, appendage, supplement, increment, augmentation, extension: This addition contributes nothing to the manuscript. 4) extension, ell, Brit annexe, US annex, wing: We used our lottery winnings to pay for an addition to the house. --prep. 5) in addition to. as well as, besides, beyond, over and above: In addition to books, the shop sold greetings cards. ---adv.phr. 6) in addition. moreover, furthermore, additionally, besides, withal, to boot, in or into the bargain, too, also, as well: We were compelled to exercise every morning and in addition we went for a ten-mile run each Saturday.