Deathly

Adjective

 * 1) Appearing as though dead, or on the verge of death.
 * He has a deathly pallor.
 * 1) fatal, causing death
 * 2) extreme
 * He has a deathly fear of crocodiles.

Adverb

 * 1) With reference to death
 * He was deathly afraid of crocodiles.
 * 1) extremely, dreadfully
 * The water was deathly cold.

Thesaurus
a la mort, abominably, agonizingly, appalling, awfully, baldly, balefully, baneful, bitterly, blatantly, blue, brashly, brutal, cadaverous, confoundedly, corpselike, cruelly, damnably, dead, deadened, deadly, death-bringing, deathful, deathlike, deathly pale, destructive, deucedly, distressingly, dolorously, dreadful, dreadfully, eerie, egregiously, excessively, excruciatingly, exorbitantly, extravagantly, fatal, feral, flagrantly, frightfully, ghastly, ghostlike, ghostly, grievously, grisly, gruesome, haggard, hellishly, horrible, horribly, improperly, inexcusably, infernally, inordinately, internecine, intolerably, killing, lamentably, lethal, livid, lurid, macabre, malign, malignant, miserably, mortal, mortuary, nakedly, openly, painfully, pale, pernicious, pestilent, pestilential, piteously, sadly, savage, shatteringly, shockingly, something awful, something fierce, sorely, staggeringly, terribly, to the death, torturously, unashamedly, unbearably, uncanny, unconscionably, unduly, unearthly, unpardonably, virulent, wan, wasted, weird, woefully