Source: Spenser, Edmund. The Faerie Queen: Book One. Ed. and Introd. Carol V. Kaske. Indianapolis: Hackett Publishing Company, Inc, 2006. Kindle version.
Words or phrases that are commonly used to the point where they lose potency.
Euphemism
Words or phrases that refer indirectly to other things, often to mask things that might be offensive (profanity, sexuality, bodily functions) or soften things that might be upsetting.
Idiom
Well-known words and phrases with literal meanings that do not match their connotations or implied meanings.