[1] : The Collaborative International Dictionary of English v.0.48

assail \assail"\ a^ss=al", v. t. imp.  p. p.
   assailed -s=ald"; p. pr.  vb. n. assailing. oe.
   assailen, asailen, of. asaillir, assailler, f. assaillir; a
   l. ad + saillir to burst out, project, fr. l. salire to
   leap, spring; cf. l. assilire to leap or spring upon. see
   sally.
   1. to attack with violence, or in a vehement and hostile
      manner; to assault; to molest; as, to assail a man with
      blows; to assail a city with artillery.
      1913 webster

            no rude noise mine ears assailing.    --cowper.
      1913 webster

            no storm can now assail
            the charm he wears within.            --keble.
      1913 webster

   2. to encounter or meet purposely with the view of mastering,
      as an obstacle, difficulty, or the like.
      1913 webster

            the thorny wilds the woodmen fierce assail. --pope.
      1913 webster

   3. to attack morally, or with a view to produce changes in
      the feelings, character, conduct, existing usages,
      institutions; to attack by words, hostile influence, etc.;
      as, to assail one with appeals, arguments, abuse,
      ridicule, and the like.
      1913 webster

            the papal authority . . . assailed.   --hallam.
      1913 webster

            they assailed him with keen invective; they assailed
            him with still keener irony.          --macaulay.
      1913 webster

   syn: to attack; assault; invade; encounter; fall upon. see
        attack.
        1913 webster
see also:
assailed assailing sally attack 

[2] : WordNet (r) 2.0

assail
     v 1: attack someone physically or emotionally; "the mugger
          assaulted the woman"; "nightmares assailed him
          regularly" syn: assault, set on, attack
     2: launch an attack or assault on; begin hostilities or start
        warfare with; "hitler attacked poland on september 1, 1939
        and started world war ii"; "serbian forces assailed
        bosnian towns all week" syn: attack ant: defend
     3: attack in speech or writing; "the editors of the
        left-leaning paper attacked the new house speaker" syn: attack,
         round, lash out, snipe, assault
see also:
assault set on attack defend round lash out 
snipe 

[3] : Moby Thesaurus II by Grady Ward, 1.0

60 moby thesaurus words for "assail":
   ambush, assault, attack, blister, blitz, bushwhack, castigate,
   censure, come at, come down on, crack down on, criminate,
   cry out against, cry out on, cry shame upon, descend on,
   descend upon, excoriate, fall on, fall upon, flay, fustigate,
   gang up on, go at, go for, harry, have at, hit, hit like lightning,
   implicate, impugn, incriminate, inculpate, involve, jump, land on,
   lash, lay at, lay hands on, lay into, light into, mug, pitch into,
   pounce upon, pound, roast, sail into, scarify, scathe, scorch,
   set on, set upon, skin alive, slash, strike, surprise,
   swoop down on, take the offensive, trounce, wade into

Assail >> A Words
Assail, definition of term: Assail
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