ominous

As adjectives the difference between ominous and mysterious

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while mysterious is of unknown origin.

As adjectives the difference between ominous and mystical

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while mystical is relating to mystics or mysticism.

As adjectives the difference between ominous and ghastly

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while ghastly is like a ghost in appearance; deathlike; pale; pallid; dismal.

As an adverb ghastly is

in a ghastly manner.

As adjectives the difference between ominous and infamous

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while infamous is having a bad reputation, disreputable; of bad report; notoriously vile; detestable; widely known, especially for something bad.

As adjectives the difference between ominous and inexorable

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while inexorable is unable to be persuaded; relentless; unrelenting.

As adjectives the difference between odious and ominous

is that odious is arousing or meriting strong dislike, aversion, or intense displeasure while ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant.

As a verb warning

is .

As a noun warning

is the action of the verb warn; an instance of warning someone.

As an interjection warning

is used to warn of danger in signs and notices.

As an adjective ominous is

of or pertaining to an omen or to omens; being or exhibiting an omen; significant.

As adjectives the difference between spooky and ominous

is that spooky is eerie, or suggestive of ghosts or the supernatural while ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant.

As adjectives the difference between ominous and omnibus

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while omnibus is containing multiple items.

As a noun omnibus is

a vehicle set up to carry many people (now usually called a bus).

As a verb omnibus is

to combine (legislative bills, etc.) into a single package.

As adjectives the difference between ominous and nefarious

is that ominous is of or pertaining to an omen or to omens; being or exhibiting an omen; significant while nefarious is sinful, villainous, criminal, or wicked, especially when noteworthy or notorious for such characteristics.