Most doggoned; the superlative form expressing the utmost degree of annoyance or damnation.
From doggoned plus the superlative suffix -est, making the highest degree form like 'saddest' or 'maddest'.
The superlative 'doggonedest' gives you 'the most doggoned thing ever'—it's almost quaint how euphemisms get their own comparative and superlative forms, preserving politeness all the way up!
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