The obvious answer is "a meal which is hot", but when I see this phrase it often seems as if there is a deeper meaning present, as if there is some major distinction between hot meals and other meals (cold meals? lukewarm meals?).
E.g. (from the Wikipedia article "Lunch"):
In Finland, lunch is a full hot meal, …
In Romania, lunch (prânz in Romanian) is the main hot meal of the day.
These usages seem to use "hot meal" as carrying a substantial quality, that the temperature of the food involved is somehow associated with its quantity or ability to satiate hunger. Is there some such association?
What does "hot meal" mean?
Best Answer
A hot meal is one that is prepared and cooked, as distinct from a sandwich, say, or some cheese with a piece of fruit.
In some countries, it has been the custom to set aside a couple of hours in the middle of the day for the mid-day meal, which allows the mid-day meal to be a full meal rather than something quickly prepared, requiring no cooking, that could be fit into a relatively brief "lunch hour".
P.S. For attestation that "hot meal" has the long-established meaning I've said it has and is not a mere "slang" term as @Kris alleges (see comment below, if @Kris has not already eaten it) see Meals in Science and Practice: Interdisciplinary Research and Business ... (H L Meiselman, ed.)
See also Food Cultures of the World Encyclopedia ( Ken Albala, ed).