The word "phantomic" is used to describe something that seems to exist but actually does not. Synonyms for this word include elusive, illusory, shadowy, imaginary, and ghostly. Elusive refers to something that is difficult to grasp or pin down, while illusory implies that something is based on an optical illusion or is unreal. Shadowy emphasizes the darkness or lack of light, and imaginary suggests something that only exists in the mind. Ghostly is used to describe something that is eerie or supernatural, often associated with ghosts. Overall, these synonyms convey the mysterious and intangible nature of something that is phantomic.