菩 (pú): This character is almost exclusively used as part of the word `菩萨`.
萨 (sà): This character is also used as part of `菩萨`. Together, `菩萨 (púsà)` is a loanword from Sanskrit “Bodhisattva,” an enlightened being in Mahayana Buddhism who delays their own nirvana to help others achieve enlightenment. The most famous example in China is Guanyin (观音), the Bodhisattva of Compassion.
心 (xīn): Means “heart,” “mind,” or “core.” It represents a person's innermost feelings and thoughts.
肠 (cháng): Means “intestines.” In classical Chinese, the combination 心肠 (xīncháng) refers to one's disposition, nature, or conscience—the “heart” in a figurative sense.
The characters combine literally to mean “Bodhisattva's heart/disposition.” It paints a vivid picture: someone's inner nature is as pure, merciful, and selfless as that of a revered Buddhist saint.
Connotation: Overwhelmingly positive. It is a term of deep respect and admiration.
Formality: Appropriate for both informal conversation and more formal writing (like in a character reference or a eulogy). Because it's such a strong compliment, it's used sincerely and not thrown around lightly.
Common Contexts:
Describing Elders: Often used to describe a kind, caring grandmother or grandfather who dotes on everyone.
Praising Caregivers: A perfect term for a dedicated doctor, nurse, or teacher who goes above and beyond for their patients or students.
Acknowledging Selflessness: Used for someone who adopts stray animals, donates significant time or money to charity, or helps a stranger in a big way.
It is slightly more common to use it to describe women, perhaps due to the association with Guanyin, the female Bodhisattva of Mercy, but it is perfectly acceptable to use for any person demonstrating profound compassion.