means To cook food with dry heat in an oven or over a flame — or, more recently, to mock someone with affectionate, escalating insults, often in front of a crowd.

from From Old French 'rostir,' to roast or burn, which itself likely came from a Germanic root — possibly related to a word for the gridiron or grate the meat sat on. English took it in around the 13th century, strictly for cooking. The 'tease mercilessly' sense came centuries later, slang that compared a person squirming under verbal heat to meat turning on a spit — and by the 20th century the comic 'roast,' a banquet of cheerful abuse, made the metaphor an institution.