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repetitious; long-winded; tedious; wordy; verbose; insistent; importunate
heavy (taste); (overly) rich; strong; cloying
gaudy (colour, design, etc.); loud
同じ話を何度もするのはくどいと思われる。
Repeating the same story is seen as tedious.
彼の説明は諄くて聞いていられない。
His explanation is so long-winded I can't listen.
くどい言い訳は逆効果になることもある。
Long-winded excuses can backfire.