Something that is menacing is threatening or suggestive of coming danger. If you’re backing away slowly from something, you can probably use the adjective menacing to describe it!
Menacing means “threatening” — whether it’s on purpose or not. A menacing tone is intended to scare you, but that menacing raincloud isn’t actually trying to ruin your day. Menacing can describe the behavior of a menace, but only the mean or dangerous kind — not just a pest: "The raccoon that always knocks over your garbage can is a menace, but it's not menacing (unless it also chases you around your house)."
