Pediment

noun (countable)

/ˈpɛdɪmənt/

A gently inclined, thinly veneered bedrock surface extending from the base of a mountain front into an arid or semi-arid basin, formed by the lateral erosion and retreat of the mountain scarp rather than by downcutting. Pediments slope gently and may be mantled by a thin veneer of transported gravel; they are major landforms of desert geomorphology, distinguishable from alluvial fans by their bedrock substrate. In India, pediments are well developed around the Aravalli Range and in parts of the Deccan Plateau margins.

✍️ Usage in a UPSC answer

The coalesced pediments flanking the Aravalli Range in Rajasthan represent a classic example of pedimentation in a semi-arid environment, where scarp retreat rather than valley downcutting governs long-term landscape denudation.

Synonyms

rock pedimenterosional slopebahada (where alluvium-covered)apron slopepiedmont slope

Antonyms

alluvial fanfloodplaindeltaoutwash plain (all depositional)

🌱 Word Family

pediment (noun), pediplain (noun, coalesced pediments), pedimentation (noun), pedimented (adjective), pediplain (noun)

🔡 Root

Borrowed from architecture, where it names the triangular gable above a classical portico

📜 Etymology

The geological term was borrowed from architecture, where pediment refers to the triangular gable above a classical Greek or Roman portico. The geological sense likens the gently sloping bedrock apron at the mountain foot to the triangular base of a classical building.

🧠 Memory Hook

PEDIMENT starts like PEDestrian: you could walk up its gentle rocky slope to the foot of a desert mountain (a memory aid only; the word itself comes from architecture).

🌍 Geography 📖 Seen in: Plate Tectonics and Volcanism…

Relevant across:GS1 · History, Geography & Society

Tip: press Alt+S to hear pronunciation