Select the most appropriate one-word substitution for the given group of words.

Something that has an unpleasant smell or taste 

Rancid

The most appropriate one-word substitution for "something that has an unpleasant smell or taste" is rancid.

• Reticent means hesitant or reluctant to say or do something.
• Stale means not fresh or not new.
• Codicil is a supplement or addition to a will.
• Rancid means having an unpleasant smell or taste, especially because of being old or spoiled.