ha-ha
HAH-hah
A sunken fence or wall set in a ditch, invisible from the house side, that prevents livestock from approaching a manor or garden while preserving an uninterrupted view of the landscape beyond. The ha-ha creates the illusion that the lawn flows seamlessly into the parkland — no barrier visible, just a sudden, hidden drop. The name supposedly comes from the exclamation of surprise upon discovering the ditch.
Etymology
French, possibly from haha, an exclamation of surprise. In use since the early 18th century in English landscape design, championed by Capability Brown and other practitioners of the "natural" garden.
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