臿 is not used independently in modern Chinese. It pictures a pestle 千 thrust into a mortar 臼 - pounding grain to husk it. It survives as the phonetic and meaning core of 插 (to insert) and 锸 (a spade).
register
Archaic only - seen in etymology notes and old texts, not in modern writing or speech.
Components
ideograph
臿chā
to husk grain; pestle in mortar
Read as one fused unit: a pestle shape 千 driven into a mortar 臼, picturing the pounding of grain. Indexed under Kangxi radical 臼. The whole graph is the phonetic in 插 and 锸.
Filed under radical 臼 (jiù, #134) by convention. 臼 is not a separate component in 臿, so no strokes are highlighted.
