Bitter and acrimonious both describe a person’s nature, speech, or behavior as harsh with anger, resentment, or cynicism. Bitter suggests a deep dissatisfaction or disillusionment that has turned into a resentful or cynical grudge against someone or something–or everything–as if experience had left a bad taste in one’s mouth: her failed dreams had made her bitter. The tone of a bitter debate would be hateful, angry, or sarcastic. An acrimonious debate suggests an angry, even vicious exchange that may also be bitter, but generally is less rooted in personal resentment. However, given the frequent occurrence of acrimonious together with divorce there can be plenty of bitterness signalled by the word acrimonious.

Smooth has a number of meanings, most with positive connotations about texture or motion (smooth skin, smooth flight, smooth transition). However, when it’s used of a person or a person’s manner or speech, which is also suave’s domain, it can skew negative and suggest a pleasing, easy manner that is self-interested or manipulative (smooth talker, smooth operator), even if requiring admirable skill: He’s smooth, I have to admit! Suave, from a Latin word meaning “sweet,” suggests a smoothly agreeable and sophisticated manner or style. Its smoothness is a polished, confident, but inoffensive easiness and gentleness that pairs well with “sophisticated” and “debonair.” It can apply as much to appearance as to manner: looking suave in his white linen suit. Men, especially actors, are more likely than women to be called suave.

Sharpen and hone refer to increasing the fineness of a point or thinness of a cutting edge on a tool to increase its effectiveness. Sharpen is the everyday word we apply to knives, blades, edges, pencils, and claws. It’s also commonly extended to mean improving an ability or skill. A challenge that sharpens your skills improves them, so that you can do a better job with them. Now, something that needs sharpening could be dull, whereas hone often suggests making something sharp even sharper. A hone is a whetstone (sharpening stone) of particularly fine, closely-packed grain. The verb has a literal definition (honed my carving knife), but most often refers to refining, polishing, and perfecting skills, techniques, or abilities, as in difficult assignments that honed our critical thinking skills.