丩 is not used on its own in modern Chinese. It pictures two strands twisting together, the original graph for entangling. A silk radical 纟 was added to give the modern 纠 (to twist, to correct), and the same shape is the phonetic in 叫 and 收.
register
Archaic only — encountered in palaeography and etymology notes, never in modern writing.
Components
ideograph
丩jiū
to twine; entangle
Just two strokes hooking into each other, picturing two cords twisted together. Indexed under Kangxi radical 丨 by tradition. Adding silk 纟 gives 纠; it is also the sound in 叫.
Filed under radical 丨 (shù, #2) by convention. 丨 is not a separate component in 丩, so no strokes are highlighted.
