Something described as gossamer—such as a butterfly wing or a thin fabric—is very light or delicate.

// Except for a few gossamer clouds, the sky was clear and blue.

To fret is to worry or be concerned.

// I was sure we wouldn’t get there in time, but they told me not to fret.

Chthonic means "of or relating to the underworld." It is used as a synonym of infernal.

// Cleo compared entering her brother's basement bedroom to a descent into chthonic regions: it was dark and odd-smelling, and she was a little frightened of what she might find there.

Feckless describes people or things that are weak or ineffective.

// The agency’s response to the dramatic increase in air pollution was well-intentioned but ultimately feckless.

If something written, spoken, or otherwise communicated is described as lucid, it is very clear and easy to understand. A person described as lucid is able to think clearly. Lucid is also used to describe things that are luminous, or that are visually transparent.

// The film conveyed a lucid message that was hard to misinterpret. // Brenna marveled at the sea stars and urchins she could see through the lucid water of the rock pool.

To deter someone is to discourage or prevent them from acting. To deter a thing is to stop or limit it.

// The heavy fines aim to deter people from dumping garbage here.

// The device is designed to deter automobile theft.

Jerkwater means “remote and unimportant.” It is often used to describe a small town, village, etc., that is out in the country far from cities. Jerkwater can also mean “trivial.”

// I grew up in a jerkwater town in the middle of nowhere.

To rue something is to feel penitence, remorse, or regret for it. Rue is often used in the phrase "rue the day."

// I rue the day I signed that infernal contract.