硌 = 石 (stone radical) + 各. The stone radical is the giveaway: it's specifically about a hard object pressing into flesh. Think of stepping on a Lego brick: that sensation is 硌.
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Colloquial, pronounced gè in this 'press uncomfortably' sense. The character also has a literary reading luò (in 硌牙 'gritty against teeth'), but spoken Mandarin almost always uses gè.
石 is the stone radical and gives 硌 its image, a pebble or stone pressing uncomfortably against skin or shoe. The verb captures the feeling of something hard digging in. Same radical in 砍, 碰, 破, stone-and-impact vocabulary.
各 gives the sound gè exactly, same tone. The 'each' meaning is irrelevant here, pure phonetic borrowing. Same series gives 路, 客, 格, all sharing similar endings from old Chinese.
