Now, you might object that I should have said 'damned thing', not 'damn thing'. After all, thing is a noun, and we expect its modifier to be an adjective; and the -ed suffix converts the verb damn into the adjective damned. (Just like the verb tire is converted into the adjective tired, the verb spoil is converted into the adjective spoiled, and so on.)However, there is an issue here. It is actually rather common for the final /d/ in a word to be omitted if it is both preceded and followed by a consonant, and this includes instances where the word-final /d/ represents the -ed suffix. Alan Cruttenden (Gimson's Pronunciation of English, 2008, p. 304) lists the following phrases where the -ed suffix (pronounced as /t/ or /d/) in the first word is often omitted in standard British English pronunciation: mashed potatoes, finished now, pushed them, tinned meat, dined well, refused both, gazed past and many, many more.
Furthermore, there are many phrases where the omission of the final consonant (either /t/ or /d/) has become so common that the -ed that originally existed in the spelling is now no longer shown: ice cream, wax paper, pop corn and skim milk all originally had -ed on the first word but now generally do not, and Language Log (here) suggests that ice(d) tea, cream(ed) corn and whip(ped) cream may all be following suit and losing their -ed suffixes.
So I think that describing it as a 'damn thing' is just fine. I just wish someone would knock it down and plant some trees (or something) in its place.
