The idiom '马如游龙' (horses like swimming dragons) often describes a bustling and lively scene. It is frequently associated with the idiom '车水马龙' (carriages like flowing water, horses like swimming dragons).

The origin traces back to the Eastern Han Dynasty. After Emperor Zhang Liu Da ascended the throne, he honored his father Emperor Ming Liu Zhuang's empress, Lady Ma, as the Empress Dowager.

Empress Dowager Ma was a woman of great integrity and humility. She personally took on the task of compiling historical records, specifically the '显宗起居注' (Records of Emperor Xianzong's Daily Life). In her writings, she consciously omitted any mention of the contributions or merits of her father, Ma Yuan, and her brother, Ma Fang. This was a deliberate effort to prevent her relatives from gaining excessive power or influence.

Furthermore, when ministers suggested that Emperor Zhang bestow noble titles upon her family members, Empress Dowager Ma firmly advised against it. She explained her reasoning by saying, 'When I visit their homes, I see their gates constantly bustling with activity, with a continuous flow of carriages and horses, much like water flowing and dragons swimming. Their prosperity and influence are already evident; there is no need to grant them further official honors.'

The phrase '马如游龙' in this context vividly painted a picture of the numerous horses moving gracefully and continuously, contributing to the overall impression of a busy and influential household.