beef slices that are used for hot pot [written and colloquial]
Definitions (粵典–words.hk)
名詞
脂肪比較多,去咗骨嘅牛肉肉片;係打邊爐常見食材(量詞:塊/片/嚿) sliced boneless beef with more fat; a common ingredient in hot pot, thus commonly known as "beef in hot pot"