Synonyms for Howl:

n.

call out, cry out, chant, rage. baa, blubber, croak, happy, weep, keen, hiss. burst out, choke up, guffaw, laughter, cry/sob your heart out, dissolve into, break up. faithful, retrieve, slaver, wag, beg, snap. jeering, peal, titter. drop, gust, lash, rise, blow, catch, pick up, freshen, get up. chuckle, giggle, laugh, scoff, force a smile/laugh, snigger, snicker. Ouch, OW. bark (noun)
grunt, snarl.
bay (noun)
ululation.
communication (noun)
howling, ululation.
cry (noun)
groan, howling, meow, whinny, caw, moo.
howl (noun)
ululate, wail, wrawl, yammer, howling, roar, yowl, ululation, yawl.
hurrah (noun)
whoop.
laugh loudly (noun)
roar.
moan (noun)
lament.
outcry (noun)
scream.
ululation (noun)
chatter, snarl, squawk, gobble, bleat, growl, chirp, bark, cackle, warble, honk, bay, yelp, bray, bellow, moo, call, squeal, whinny, purr, bawl, caw, mew, roar, cuckoo, cluck, meow, cry, ululation, quack, twit, hoot, snort, coo, neigh, grunt, crow, trill.

v.

bark (verb)
cry, snap.
bawl (verb)
call, cheer, holler.
bellow (verb)
bray, whoop.
body (verb)
roar.
call (verb)
cry out, exclaim.
communication (verb)
yawl, ululate, roar, wail.
cry (verb)
whoop, groan, shriek, cheer, scream, holler, clamor, yell, shout, exclaim, moan.
ululate (verb)
chatter, snarl, squawk, gobble, bleat, growl, chirp, bark, cackle, warble, honk, bay, yelp, bray, bellow, moo, call, squeal, whinny, purr, bawl, caw, mew, roar, cuckoo, cluck, meow, cry, ululate, quack, twit, hoot, snort, coo, neigh, grunt, crow, trill.

Other synonyms:

choke up, OW, freshen, snigger, chuckle, scoff, snicker, Ouch. blubber, croak, cry out, guffaw, weep, wag, titter. giggle, slaver, beg, gust, retrieve. hiss, snap. faithful. peal, get up. lash. blow. pick up. rise. drop. chuckle
laugh.
cry
hoot, weep.
lament
lament.
laugh
snicker.

Usage examples for howl

  1. Then a howl of protest, offers of huge sums of money, for the most part put forward by men without a dollar to their names, on the result of the city vote; finally a strident voice, repeating over and over again, " He can't beat the Combine!" – Loaded Dice by Ellery H. Clark
  2. Just You shall howl if you lay your hand on him. – The Clouds by Aristophanes
  3. At evenin's after supper when the wind'd howl around the house she'd make it sound like Heaven in here. – Dramatic Technique by George Pierce Baker