Synonyms for Ghost (same or very similar meaning)
WordNet sense 1 (a writer who gives the credit of authorship to someone else):
ghostwriter
WordNet sense 2 (a suggestion of some quality):
touch, trace
WordNet sense 3 (a mental representation of some haunting experience):
shade, specter, spook, wraith, spectre
WordNet sense 4 (haunt like a ghost; pursue):
haunt, obsess
WordNet sense 5 (write for someone else):
ghostwrite
From the ODE community, based on WordNet
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