What is the definition of kindness for kids? Kindness is defined as being kind with an intentional act that benefits others for its own sake when one is not required to do so. Kindness is usually regarded as a virtue. A kind person exhibits a genuine, selfless, and deep concern for people without expecting to get anything in return. Kindness allows children to form connections that are significantly associated with increased happiness. The rush of endorphins related to helping others creates a sense of lasting pride, optimism, and self-worth. This infographic shows kindness activities that your children can do to understand more about it.