The antonyms for the word "more nectarous" are bitter, sour, and unpleasant. These words are used to describe flavors that are not sweet and enjoyable, but rather harsh and unpleasant to the taste. Bitter is the opposite of nectarous, referring to a taste that is dry and harsh, while sour is a flavor that is acidic and tart. Unpleasant is a term used to describe anything that is not enjoyable or pleasing. While nectarous is used to describe delicious, sweet, and desirable flavors, these antonyms are used to describe tastes that are undesirable and unappealing.