Both words refer to something that is the only one of its kind. Unique, in this sense (it has several), suggests being the only one in existence or the only example of something: As far as we know, every snowflake is unique. Sui generis is a strong synonym for unique in this example. The translation of this phrase borrowed from Latin is “of its own kind.” Sui generis in a strict sense refers to something that does not fit into any existing category and therefore is its own category (and that category’s sole member). The European Union is said to be a sui generis organization. Sui generis often implies something that, to be dealt with, requires a new rule or approach: a sui generis situation, problem, or species. The term is used in law, biology, and other fields: a sui generis species needs its own genus. In less rigorous contexts, you can say someone has a style that is sui generis without fear of repercussions.

Both words refer to removing someone from danger or difficulty. Rescue is the more general term. It suggests the saving of a person or thing from harm or death (rescued the cat from the fire), and usually involves physically removing someone from danger and bringing them to safety. Extricate suggests freeing someone who is caught or trapped in a literal or figurative tangle. Not as straightforward as some types of rescue, extrication is often done carefully, with difficulty, or finally (at last). Some of the most frequent objects of extricate are victim, body, and driver, and the context is often a car wreck or a disaster. Extricating a country is also a common challenge—whether from a war or from debt. On the lighter side are the hairy social situations from which we often have to extricate ourselves—politely, or gracefully.

Both nouns refer to disrespectful or contemptuous words or actions that wound another’s sense of self-worth or pride. Most typically, an insult is a harsh disparaging remark that expresses low regard for someone. Insults are hurled, shouted, or traded like blows. Affront suggests an open show of disrespect towards a person, a group, or a collective value. Your aunt might consider it a personal affront to her that you didn’t let her know you were in the neighborhood, but parked right in front of her house. An affront can offend a specific human attribute (an affront to their dignity or sensibilities), and can be applied to a value (Regulation is an affront to liberty; an affront to democracy or our fundamental rights). Adjectives often paired with affront include serious, blatant, and egregious.