Final answer:
A a) euphemism is the term for a mild or indirect word used in place of one that may be considered too harsh or blunt, and it originates from the Greek word for 'good speech'.
Step-by-step explanation:
The mild word substituted for an offensive one, derived from the Greek for "good speech", is a a) euphemism.
Euphemisms are employed to soften the delivery of language concerning subjects that might be too harsh, blunt, unpleasant, or embarrassing.
In contrast to paradoxes, which are statements that seem contradictory but may reveal a truth; idioms, which are phrases with figurative meanings different from their literal ones; and metaphors, which are figures of speech that describe an object or action in a way that isn't literally.
True but helps explain an idea or make a comparison, euphemisms serve the particular purpose of providing a polite or less offensive alternative to a direct term.