Although it is a bit informal, the word “dolt” is used to name someone who is a fool or is stupid. It is related to the word “dull,” in the sense of not having a very “sharp” mind. The best antonym for this is “genius,” which is purely opposite to one who is stupid.

When we “discern” something, we are said to recognize it. For instance, we could say, “After three years of living in the monastery, the young man discerned that the way of life did not match his personality. He soon thereafter chose to leave the cloister.” Before the young man left, he discerned—recognized—the situation. A “discerning” person is someone who exhibits good judgment, likely because he or she looks for and recognizes appropriate reasons for those judgments. This is quite different than an impulsive person. Such a person acts without thinking, following one impulse after another without any direction.

Something that is distasteful causes disgust because of its unpleasant character. This can apply to foods but it can likewise pertain to things like “distasteful actions,” as in, “I find it extremely distasteful when someone wipes his nose with his hand.” The word “palatable” is related to the word “palate,” meaning “roof of the mouth,” and also “palate” in the sense of someone’s ability to discern tastes. For instance, one could say, “The wine leaves an oaky flavor on your palate.” Something “palatable” is “tasteful,” either in the literal sense pertaining to food and drink but also in the broader sense of being acceptable.

Something is called fatal when it is likely to lead to a disaster or to cause death. A “fatal wound” is one that is likely to end in the death of the person thereby wounded. In contrast to such a dangerous state of affairs, “harmless” is an adequate antonym.

Although the word “fuming” does mean the physical act of sending of vapors or fumes because of smoke, it is often used in the metaphorical sense of indicating that someone is extremely angry. In contrast to this, something that is “serene” is calm and untroubled.

When someone is a nuisance, that person is an annoyance or displeasing. We might call a bothersome classmate a nuisance if that person is always annoying us, asking for money, making rude remarks, or other things of the like. The word “pleasure” is an adequate contrast—that is, if the word is understood in the sense of, “He was an utter pleasure to be around.”

Perhaps you associate the word “gallant” with knighthood and the courageous exploits of armored men. The reason for this is that the word means “courageous” or “heroic”—a trait that we hope to find in knights and warriors.  In contrast to this, the word “cowardly” functions as an excellent antonym, as it means “lacking courage” or “regularly and easily fearful.”

To gulp something is to swallow it in large amounts all at once. While mere “drinking” or “eating” might appear to be acceptable antonyms, the word “sip” best captures a sense directly opposed to gulping. Simply sipping something is the taking of small, measured drinks.

Something that is a hassle is inconvenient, often in an irritating manner. A hassle might also be said to be bothersome or, at least in a secondary sense, cumbersome or difficult. Something that is convenient is not a hassle but instead is easy and available.

When something is horrific or horrifying, it causes shuddering and fear. Such a thing is unsettling, causing someone to be ill at ease and frightened. Thus, the best option for an antonym among the options provided is “reassuring,” for when something is reassuring, it removes fear and concern. While “lovely” and perhaps even “pictorial” might be tempting answers, only “reassuring” directly opposes this sense of frightfulness.