ha-ha

sound of laughter (used to express amusement or derision)

The ha-ha or sunken fence is a type of boundary to a garden, pleasure-ground, or park, designed not to interrupt the view and to be invisible until closely approached. The ha-ha consists of a trench, the inner side of which is vertical and faced with stone, with the outer slope face sloped and turfed - making it in effect a sunken fence. The two syllables may also refer to the onomatopoeia which represents the sound of light or sarcastic laughter.
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Noun
1. a loud laugh that sounds like a horse neighing
(synonym) hee-haw, horselaugh, haw-haw
(hypernym) laugh, laughter
2. a ditch with one side being a retaining wall; used to divide lands without defacing the landscape
(synonym) sunk fence, haw-haw
(hypernym) ditch

(n.)
A sunk fence; a fence, wall, or ditch, not visible till one is close upon it.
  

intj.
آہا, کيا خوب, واہ واہ, اے واہ, ہاہا, اوہو, واچھڑے, سبحان الله, افسوس, ہائے ہائے, ہائے, حيف
ha-ha
n.
کھائي, خندق