“Anti-mattering” is the persistent belief that one is invisible, inconsequential, and does not matter to anyone. It differs from temporary feelings of being overlooked or unappreciated because it’s more enduring and corrosive.

Attunement is the experience of feeling deeply understood and meaningfully responded to by another person. Attunement involves paying close attention to another person’s emotional state and responding in a way that reflects what they need in a particular moment.

A “cornerman” is a metaphor for someone who is personally invested in another person’s success and understands their strengths and vulnerabilities. Borrowed from boxing, the term describes someone who can view another person’s situation from an outside perspective, offer honest advice, and remind them that they aren’t facing difficulties alone.

Ego extension is the feeling that another person is genuinely invested in one’s well-being, successes, and struggles. Ego extension works in both directions, with each person becoming invested in the experiences, happiness, and struggles of the other.

A “helper’s high” is the increase in vitality that can result from helping other people. The term describes the positive effect that helping others can have on the helper’s own energy.

An “impact file” is a personal collection of reminders that one’s efforts have made a difference in other people’s lives. It may contain thank-you notes, emails, messages, photographs, cards, or other forms of appreciation that serve as reminders of the difference one makes in others’ lives.

“Mattering” is the feeling of being valued while also knowing that one has value to add to the world. It includes the assurance that one’s presence and actions are significant to others.

A “mattering core” is a sturdy internal sense of being valued by family, friends, colleagues, and one’s community while knowing how one adds value in return. The mattering core consists of five elements: Recognition, Reliance, Importance, Ego Extension, and Attunement.

“Mattering leadership” is an approach to workplace culture centered on everyday actions that affirm a colleague’s value. Employees at any level can practice mattering leadership and contribute to creating a culture in which colleagues feel that they matter.

A “mattering lens” is a way of examining experiences of diminished mattering by identifying which element of the mattering core has been affected. The lens considers recognition, reliance, importance, ego extension, and attunement to help identify the underlying need that has been disrupted.

“Mattering practices” are rituals designed to make individuals feel valued. These can include coming-of-age ceremonies and retirement celebrations, which offer a sense of belonging and purpose and remind participants that their existence holds meaning.