磕

to tap / to knock (against sth hard) / to knock (mud from boots, ashes from a pipe etc)

variant of 嗑[ke4]

variant of 盍[he2]

why not

surname Shi / abbr. for Shijiazhuang 石家莊|石家庄[Shi2 jia1 zhuang1]

dry measure for grain equal to ten dou 斗 / ten pecks / one hundred liters

rock / stone / stone inscription / one of the eight categories of ancient musical instruments 八音[ba1 yin1]

dry measure for grain equal to ten dou 斗[dou3]; one hundred liters / ancient pr. [shi2]

bumpy (of a road) / limping (of a person)

to kowtow (traditional greeting, esp. to a superior, involving kneeling and pressing one's forehead to the ground)

to knock against / to bump into / to have a disagreement / to clash

(slang) to revel in the sight of one's favorite couple being affectionate / to lap it up when one sees a couple whom one ships kissing or cuddling

(dialect) knee

lit. to kowtow like grinding garlic (idiom) / fig. to pound the ground with one's head

(coll.) to fight to the death

(onom.) knocking

stammering / stuttering / not speaking fluently