叩

三跪九叩

sān guì jiǔ kòu

to kneel three times and kowtow nine times (formal etiquette on meeting the emperor)

叩应

kòu yìng

call-in (loanword)

叩拜

kòu bài

to bow in salute; to kowtow

叩球

kòu qiú

spike (volleyball)

叩问

kòu wèn

(literary) to inquire

叩见

kòu jiàn

to kowtow in salute

叩谒

kòu yè

to visit (esp. one's superiors)

叩门

kòu mén

to knock on a door

叩关

kòu guān

to knock at the gate (old)

叩头

kòu tóu

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

叩首

kòu shǒu

to kowtow

跪叩

guì kòu

to kowtow