In Southern topolects - Cantonese, Hokkien, Hakka - the verb 'to eat' is 食 (sik6/chia̍h) rather than 吃. You'll see 食饭 on HK/Taiwan/Guangdong menus and signs; Mandarin 普通话 drops 食 in favor of 吃.
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Classical Chinese also used 食 for 'eat' (食不语，寝不言 - Confucius). So 食饭 is both a Southern colloquialism AND the historically older form, glossed simply as 'a meal.'
