threat ‧ en ‧ ing /ˈθretn-ɪŋ/ BrE AmE adjective
[ Word Family: verb : ↑ threaten ; noun : ↑ threat ; adverb : ↑ threateningly ; adjective : ↑ threatening ]
1 . if someone’s behaviour is threatening, you believe they intend to harm you:
His voice sounded threatening.
a threatening gesture
2 . if the sky or clouds are threatening, bad weather is likely:
a threatening thundercloud
—threateningly adverb