"ghastly white" is a correct and usable phrase in written English.
It can be used to describe something that is extremely pale or deathly white in appearance. Example: The ghostly figure appeared before him, its face ghastly white and its eyes empty of life.
Last year the trees were a hideous, ghastly white.
After a while, Gibson looked up at me, his face ghastly white.
He would teeter on stage, perched on a pair of green spike-heeled shoes, face painted ghastly white, cheeks bright red with rouge.
"A pinprick of brilliant light punctured the darkness, spurted upward in a flaming jet, then spilled into a dazzling cloche of fire that bleached the desert to a ghastly white," Mr. Lamont wrote.
A ghastly white sludge called total parenteral nutrition had to be fed to me intravenously, which gave me essential nutrients and minerals to keep me going, but wasn't exactly the post-transplant feast I had imagined.
Placards are already piled high, and folded banners and cards of lapel buttons and whistles, football rattles and trumpets, funny hats and rubber masks of politicians — Bush and Blair in wobbling stacks, the topmost faces gazing blankly skyward, ghastly white in the sunshine.
And if giant, ghastly-white fanged maggots were not enough, they transformed into giant flies, which could squirt a poisonous liquid.
There a hermit the local people call Old Whaley — "rail thin, skin the ghastly gray-white of a fish belly" — offers her shelter.
After a single baptism in your vats, my sky-blue jibbahs faded to a ghastly greenish-white and the fabric evaporates under one's touch….
(Mr. Coben has dreamed up a ghastly middle-aged white Jersey rapper calling himself Ten-a-Fly).
Now the use of a ghastly weapon called white phosphorus has raised questions about how careful the military has been in avoiding civilian casualties.
