Somewhat ghost-like or having qualities resembling those of a ghost; vaguely spectral or eerie.
From 'ghost' + '-ish' suffix (meaning somewhat or somewhat like). The '-ish' suffix is extremely productive, creating adjectives that express similarity without exactness.
The '-ish' suffix is genius for uncertainty—'ghostish' means 'kind of like a ghost but not exactly,' which is perfect for describing things that are hard to pin down, like how we talk about colors ('bluish,' 'greenish') or ages ('twentyish').
Complete word intelligence in one call. Free tier — 50 lookups/day.