棱 most often appears in 棱角 (sharp edges and corners, figuratively a sharp personality) and 模棱两可 (ambiguous). Other readings are non-standard: lēng only in onomatopoeia like 扑棱, and líng only in the place name 穆棱.
Tree radical on the left, the indexing radical. The original 棱 was a piece of timber dressed to four sharp corners, an edged beam used in construction. It anchors the character in the timber family with 板 (plank), 柱 (pillar), 梁 (beam).
Right side 夌 supplies the sound, líng shifting to léng. It originally meant 'to climb across, to overstep', the image of an edge rising between two surfaces. Same phonetic powers 凌 (rise above), 陵 (hill, mausoleum), 菱 (water chestnut).
