Which word describes something that portends evil or has harmful intent?

The term that accurately describes something that portends evil or has harmful intent is "ominous." This word conveys a sense of foreboding or a warning sign that something bad is going to happen. It is often used in contexts where the atmosphere or events give rise to a feeling that trouble lies ahead.

While "baleful" evokes a similar idea of causing harm or being threatening, it emphasizes the malevolence or sinister aspect of something. In many contexts, baleful is used to describe actions or threats that are inherently evil or ominous. "Malicious" refers specifically to actions intended to cause harm, which is slightly different from simply portending evil. "Dreadful," on the other hand, tends to describe something that causes fear or suffering but does not inherently imply a portent of future harm.

Thus, "ominous" is the word that best fits the definition of indicating something evil or harmful is likely to come.