Source : Webster's Revised Unabridged Dictionary (1913)

Stock-still \Stock"-still`\, a. [CF. G. stock-still.]
   Still as a stock, or fixed post; perfectly still.

         His whole work stands stock-still.       --Sterne.

Source : WordNet®

stock-still
     adj : absolutely still; "frozen with horror"; "they stood rooted
           in astonishment" [syn: {frozen(p)}, {rooted(p)}]
     adv : without moving or making a sound; "he sat still as a
           statue"; "time stood still"; "they waited stock-still
           outside the door"; "he couldn't hold still any longer"
           [syn: {still}]