Compound Noun, Compound Adjective

Hyphenated compound nouns are fairly uncommon, but here’s an example, with a compound adjective after it. It’s a recent (February 10, 2023) Washington Post headline.

Biden ordered [a/the] shoot-down of a ‘high-altitude object’ over Alaska airspace

Headlines tend to be terse, so I added the articles in the brackets to make it easier to see that they combined a verb and a preposition to make a “shoot-down” into a noun. In English, compound nouns tend to migrate from being hyphenated (such as “pick-up”) to being a single word (pickup) as they become more common. We don’t say “a shoot-down” very often.

You can easily tell that “high-altitude” is an adjective because it refers to “object.”

Sorry, no picture of the object yet. [later] Okay, here’s a photo. The balloon is the white circular object.