Here's what rhymes with defail.
fail sale sail veil hail shale vale hale faille detail male scale mail pale tail tale avail jail nail prevail rail frail gale whale bail stale wail assail bale dale inhale pail snail flail bewail derail kale wale trail entail email travail quail exhale quale braille topsail unveil grail impale taffrail wassail hightail curtail mainsail pigtail foresail bobtail pellmell lugsail carrell gunwale ponytail countervail martingale monorail hangnail fingernail nonpareil swallowtail tattletale