IPA: /ˈroʊstər/
KK: /ˈroʊstər/
A tool or device used for cooking food, especially meat, by exposing it to heat, often in an oven or over an open flame.
The chef used a large roaster to prepare the Thanksgiving turkey.
Roaster → It is formed from "roast" (from Old French *rostir*, meaning to cook by exposure to dry heat) and "-er" (meaning a person who). A roaster is a person or device that cooks food by roasting.
Think of someone who 'cooks by dry heat' ('roast') — the '-er' indicates a person, so a roaster is someone who roasts food.