This could be either
1. Gongshou Li (拱手礼)
Gongshou Li, also know as Fist and palm salute, is one of formal greeting etiquettes in ancient China. It is commonly used in daily occasiions (meeting and parting, when offering thanks or apologies).
When Chinese bow they make a half-fist with their hand and hold it in the palm of the other hand at stomach level and bow slightly to deeply depending on how much respect they want to convey. Noted that, for male: right-hand half-fist and left hand on top, for female: opposite way. Although in funeral, the greeting should be done on the other way around: Right-hand on the top for men and left-hand on top for women.
Example: post #844620
2. Baoquan Li (抱拳礼)
Baoquan Li, also know as Kung Fu Salute, Hold palm salute or Hold fist salute, is a common etiquette derived from (but not exclusive to) Chinese Martial Arts. It shows the humility and often widely used among the kung fu masters and students.
This salute is generally characterised by an open left hand placed next to a closed right fist. The importance is that the fingers on the left hand should stay extended and not flexed to cover the right fist.
Example: post #2872432
- Chinese Customs, Manners and Etiquette
- Chinese Etiquette: Fist and palm salute (and the difference between Gongshou Li and Baoquan Li)
Origins and Meaning of the Kung Fu Salute by Shuai Zheng (2012)