Simple past tense and past participle of butter.(verb)
Spread with butter.(adjective)
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Use "buttered" in a sentence
"Plain - buttered and grilled on both sides, TEXAS TOAST."
"And I burnt off 290 calories according to my fab pedometer (which Paul insists as pronouncing as paedo-meter and now every time I write or think the word it comes out like that, damn his eyes), and I've just eaten the 290 calories back in buttered toast."
"Apparently they get their bread buttered from the terrorists themselves."