The word "刀俎" is formed by directly combining the character "刀", meaning knife, with "俎", meaning cutting board, both of which are concrete nouns referring to utensils used in tandem for cutting meat. This juxtaposition creates a compound word that denotes the collective tools for butchering, and by extension, it idiomatically represents a scenario where one is subjected to the control or harm of another, derived from their functional association in a literal context.