Euphemism – substitute strong word for milder one

Euphemism is the substitution of a milder, vaguer word for one considered to be offensive or unpleasant.

“That’s just a youth’s mist.” (euphemism).

“No, it’s a fart!”

Examples

“They are academically challenged” is a euphemism for stupid.

“Adult entertainment” instead of pornography.

“Between jobs” instead of unemployed.