Meaning:
“谐音” means “homophone,” and “梗” is a misspelling of another character “哏” (gén, from Tianjin dialect) which means “jokes.” This term refers to “homophonic jokes” or “homophonic puns,” a popular form of jokes shared online or told by comedians.
Example:
A: 讲个笑话来听听。
Jiǎng ge xiàohuà lái tīngting。
Tell me a joke.
B: 哈利▪波特乔装成了一个记者，准备偷袭伏地魔。
Hālì bōtè qiáozhuāng chéng le yīgè jìzhě，zhǔnbèi tōuxí fúdìmó。
Harry Potter poses as a reporter in order to attack Lord Voldemort unexpectedly.
哈利▪波特：你好我是一名记者。
Hālì bōtè：Nǐhǎo wǒ shì yīmíng jìzhě。
Harry Potter: Hi, I’m a reporter.
伏地魔 (fúdìmó)：Ha? Reporter?
Lord Voldemort: Ha? Reporter? (Ha-rrypotter?)
哈利▪波特：还是被你发现了！
Hālì bōtè：Háishì bèi nǐ fāxiàn le！
Harry Potter: You got me!
A: 这个谐音梗有意思。
Zhège xiéyīngěng yǒuyìsī。
This homophonic pun is funny.