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What's the difference between frost, hoar-frost, rime, rime ice?

They look similar, but is there really a difference between them?

Context:

"bushes covered with frost"

"the hoarfrost formed a delicate swirly pattern on the window"

"There was a strong rime on all vegetation."

"The town looked like a lunar landscape, with everything covered in rime ice."

Thank you in advance!

Edit: Links to the definitions: https://www.macmillandictionary.com/dictionary/british/frost_1

https://dictionary.cambridge.org/dictionary/english/hoarfrost

https://www.google.com/search?q=define+rime&oq=define+rime&aqs=chrome..69i57j0i512l3j0i10i22i30l3j0i10i22i30i395.4867j1j7&client=ms-android-vf-ro-revc&sourceid=chrome-mobile&ie=UTF-8

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    Have you looked up the words in a dictionary? Why should we have to do all the work??
    – Lambie
    Commented Feb 1, 2022 at 20:50
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    Welcome! 1) Yes, please edit to show what you find in dictionaries. For one thing, it will help us supplement them better. 2) Be aware that some of these are much less common than others. Not invalid, but rare. "Frost" is extremely common; "hour-frost" much less so, and "rime" fairly obscure (I once tried to use "rimy" in a magazine article and the editor changed it to "grimy"). I haven't actually heard the usage "rime ice" before.
    – Andy Bonner
    Commented Feb 1, 2022 at 21:13
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    A dictionary will tell you the differences. What sort of audience are you writing for? For a general audience, "frost" will probably work in all contexts. For a specialist meteorologist, there is a technical difference. What experience do you have with frost? Do you come from a country in which frost is common?
    – James K
    Commented Feb 1, 2022 at 21:26
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    The word hoar is also used alone. M-W *b : a covering of minute ice crystals on a cold surface *.
    – Jack O'Flaherty
    Commented Feb 2, 2022 at 0:49
  • 2
    This is a science question, not an English language question.
    – Astralbee
    Commented Feb 2, 2022 at 8:45

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This is a little like asking for the meaning of "cat", "serval" and "ocelot". Most people know that ocelots and servals are types of wild cat, but couldn't distinguish them.

Frost is a general term for the ice that forms on many things when the temperature is below zero. This is normally the word to use. It is distinguished from "snow" (which falls from the sky) and the ice that grows on puddles, ponds, and lakes.

Hoar, or hoarfrost is a type of frost. It has a "feathery" appearance. It forms when water vapour changes directly to ice.

Rime is a type of frost, it forms when water droplets in mist touch cold objects and freeze. It tends to be harder than hoar. It can also be a verb meaning "to cover with frost"

In non-technical language, there is a lot of technically inaccurate use. Most people don't inspect frost closely enough to decide if it is hoar or rime, and don't really know the technical definitions. In your examples, the window ice isn't technically hoarfrost, and it is common enough to see examples like "rimed with hoarfrost".

So for many people, these are "types of frost" but they don't know the difference between them.

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