Is there a verb form of the word ominous?

While "ominous" is an adjective, there isn't a direct verb form of it. However, you can use verbs that convey a similar meaning:

* Forebode: This implies a sense of foretelling something bad or ominous. "The dark clouds foreboded a storm."

* Portend: This suggests something that serves as a warning or sign of something bad to come. "The sudden silence portended danger."

* Presage: This means to be a sign or warning of something that will happen, often something bad. "The eerie stillness presaged disaster."

* Threaten: This indicates a danger or possibility of harm. "The storm clouds threatened to unleash a torrent of rain."

You can also use phrases to express an ominous quality, such as:

* Cast an ominous shadow over

* Be heavy with ominous significance

* Feel ominous about

Choose the verb or phrase that best suits the context and the level of ominousness you want to convey.