Rancid usually describes something edible that has a strong and unpleasant smell or taste because it is no longer fresh. In figurative use, rancid describes things that are very distasteful or offensive.

// The corpse flower, which is the largest known individual flower of any plant species, stays open five to seven days and emits a rancid odor.

Something described as sedentary does or involves a lot of sitting. Sedentary can also mean "not physically active" (as in "a sedentary lifestyle") or "not migratory" (as in "sedentary birds" or "a sedentary civilization").

// Editing the dictionary is a sedentary job.

Veritable is a formal adjective that means “being in fact the thing named and not false, unreal, or imaginary.” It is often used to stress the aptness of a metaphorical description.

// The island is a veritable paradise.

// The sale attracted a veritable mob of people.

When muse is used to mean "to think about something carefully or thoroughly," it is usually followed by about, on, over, or upon. The word can also mean "to become absorbed in thought," or "to think or say something in a thoughtful way."

// He mused on the possibility of pursuing a master's degree.

// "I could sell the house," she mused aloud, "but then where would I go?"

Kibosh refers to something that serves as a check or stop. It is usually used in the phrase “put the kibosh on” to mean “to stop or end (something)” or “to prevent (something) from happening or continuing.”

// I downloaded an app to help me put the kibosh on my high screen time.

To coalesce is to come together to form one group or mass.

// The club’s community service projects provide students with a common goal to coalesce around.

// The movie is full of beautifully written scenes but they never coalesce into a whole.

Utopia refers to an imaginary place in which the government, laws, and social conditions are perfect; a utopia is a place of ideal perfection.

// It’s a nice place to live, but it’s no utopia.

Penultimate means "occurring immediately before the last one," or in other words, "next to last." A formal adjective, it is always used before the noun it modifies.

// The penultimate episode of the TV series features some shocking plot twists that set up what will surely be a thrilling series finale.

the beginning of evening; twilight; dusk