梗 (gěng) — 'meme / running joke / punchline / setup'. A versatile internet word: 玩梗 wángěng (to make a joke / use a meme), 接梗 jiēgěng (to riff on a meme), 梗图 gěngtú (meme image), 烂梗 làngěng (dead/tired meme). 烂 (làn) literally means 'rotten'.
culture
Origin: 梗 was a misheard / popularized rendering of 哏 (gén) from 相声 (xiàngsheng, traditional crosstalk comedy), where 哏 means a punchline. Internet usage normalized the misspelling 梗, and now 梗 is the dominant form.