The character is two
朿 (cì, 'thorn') side by side — a thicket of thorn-bushes. Modern uses are almost always in compounds:
荆棘 (jīngjí, brambles),
棘手 (jíshǒu, thorny/tricky),
棘皮动物 (jípí dòngwù, echinoderms — 'thorn-skin animals' like sea urchins and starfish).