ghastly

Concise Oxford English Dictionary © 2008 Oxford University Press:
ghastly/ˈɡɑːstli/

▶adjective (ghastlier, ghastliest)

• 1 causing great horror or fear; macabre.

• 2 deathly white or pallid.

• 3 informal very objectionable or unpleasant.

– derivatives
ghastliness noun.

– origin ME: from obs. gast ‘terrify’, from OE gǣstan, of Gmc origin; rel. to ghost.