tending or intended to menace: threatening gestures.
causing alarm, as by being imminent; ominous; sinister: threatening clouds.

Origin of threatening

First recorded in 1520–30; threaten + -ing2
Related formsthreat·en·ing·ly, adverbnon·threat·en·ing, adjectivenon·threat·en·ing·ly, adverbun·threat·en·ing, adjectiveun·threat·en·ing·ly, adverb

Synonyms for threatening

2. See imminent, ominous. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unthreatening

Contemporary Examples of unthreatening

Historical Examples of unthreatening

  • But most of the insect world was neither so helpless nor so unthreatening.

    The Forgotten Planet

    Murray Leinster

  • Not all the insect world was so helpless or so unthreatening.

    The Mad Planet

    Murray Leinster