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entrails; guts
さんまのわたは苦みがあるが好む人も多い。
The guts of Pacific saury are bitter, but many people enjoy them.
イカのわたを使った塩辛は酒の肴に合う。
Salted fermented squid made with its entrails goes well as a snack with drinks.
鯛のわたを丁寧に取り除いてから刺身にした。
I carefully removed the guts of the sea bream before making it into sashimi.