[syn: goddam, goddamn, goddamned]
The Collaborative International Dictionary of English v.0.48:
goddam \god"dam\ goddamn \god"damn\ goddamned \god"damned\adj.
   A more intense and vulgar form of darned; -- often taken as
   profane and offensive. [vulgar]
   Syn: blasted, blessed, damn, darned, deuced.
        [WordNet 1.5]
WordNet (r) 3.0 (2006):
goddamn
    adv 1: extremely; "you are goddamn right!" [syn: goddam,
           goddamn, goddamned]
    adj 1: used as expletives; "oh, damn (or goddamn)!" [syn:
           damn, goddamn]
    2: expletives used informally as intensifiers; "he's a blasted
       idiot"; "it's a blamed shame"; "a blame cold winter"; "not a
       blessed dime"; "I'll be damned (or blessed or darned or
       goddamned) if I'll do any such thing"; "he's a damn (or
       goddam or goddamned) fool"; "a deuced idiot"; "an infernal
       nuisance" [syn: blasted, blame, blamed, blessed,
       damn, damned, darned, deuced, goddam, goddamn,
       goddamned, infernal]
Moby Thesaurus II by Grady Ward, 1.0:
18 Moby Thesaurus words for "goddamn":
   absolute, accursed, blankety-blank, blasted, blessed, blooming,
   complete, consummate, cursed, damn, damnable, damned, darn,
   execrable, goddamned, infernal, outright, unmitigated