A scary man that comes at you with a gun is an example of someone who is menacing.
He picked up a menacing looking tool.
She growled in a deep, menacing voice.
He cultivated good relations with England, in view doubtless of Russia's menacing attitude.
Still more menacing became the political situation on the outbreak of the French Revolution.
It was a weary and famished, but still a fighting and menacing army.