Synonyms for Balloon:

n.

increase, add to, soar, go through the roof, raise, step up, go up. cap, action figure, bulge, protrude, bag, building block, construction paper, project, doll's house, clay, jut, overhang, stick out, catapult, beanbag, pouch, beetle, convex, stand out, belly, protuberate, dollhouse. airliner, aeroplane, b-52, Air Force One, airplane, biplane, airbus. bowl, ball, coil, crescent, circle, cone, band. drain, eeg, ecg, electrocardiograph, defibrillator, catheter, electrocardiogram, drip, ekg. grow, dilate, outgrow, wax and wane, mature, supersize, double. airplane (noun)
aircraft.
balloon (noun)
billow, inflate.
bubble (noun)
froth.
dirigible (noun)
gasbag, blimp, aircraft, montgolfier, observation balloon, lighter-than-air craft, barrage balloon, nondirigible aerostat, bag, captive balloon, zeppelin, free balloon, weather balloon, kite balloon, zep, sausage, airship, toy balloon, radar balloon.
inflated material or vehicle (noun)
blimp, zeppelin, airship.

v.

billow out; bloat (verb)
belly, dilate, inflate, bulge.
bubble (verb)
bubble, effervesce, lather, spray, foam, froth, boil, aerate, cloud, fizz.
change (verb)
billow, inflate.

Other synonyms:

beanbag, construction paper, electrocardiogram, cap, electrocardiograph, catapult, ecg, aircraft, clay, dollhouse, Air Force One, aeroplane, biplane, action figure, doll's house, ball, building block, catheter, protuberate, airbus, defibrillator, blimp, airplane, airliner. bowl, eeg, pouch, protrude, jut, overhang, belly, beetle, crescent, ekg. cone, drip. bulge, circle. coil, drain. band. airship
zeppelin.
bulge
protrude, protuberate, beetle.
dirigible
airship.
surge
billow.
Other relevant words:
airbus, protrude, airliner, beanbag, cap, protuberate, catapult, electrocardiogram, zeppelin, electrocardiograph, ball, aircraft, billow, band, grow, gasbag, catheter, inflate, barrage balloon, dilate, captive balloon, defibrillator, go up, project, stick out, weather balloon, sausage, biplane, bag, stand out, jut, airship, beetle, bulge, overhang, soar, airplane, aeroplane, blimp, lighter-than-air craft, pouch, increase, belly.

Usage examples for balloon

  1. " Then, unless she went away in a balloon where it wouldn't matter what she had on, she is still around the premises. – The Window at the White Cat by Mary Roberts Rinehart
  2. We should not have been astonished had he said on board his balloon – The Adventures of Harry Richmond, Complete by George Meredith Last Updated: March 7, 2009
  3. Then he summoned a celebrated magician, who at his orders shut the princess and sluggard up in a crystal cask, to which was fastened a balloon well filled with gas, and sent it up in the air among the clouds. – Fairy Tales of the Slav Peasants and Herdsmen by Alexander Chodsko