| sunk fence. |

ha-ha 2 (hä'hä') n. See sunk fence. [French, exclamation of surprise, ha-ha (from its being designed not to be seen until closely approached).] |
| sunk fence n. A walled ditch or sunken obstacle, such as a hedge, serving especially as a barrier to livestock without impairing the view or scenic appeal. Also called ha-ha2. |