fount
A rich, never-ending source of something valuable.
A fount is a source or origin of something, especially something that flows abundantly or continuously. When someone describes a grandmother as a fount of wisdom, they mean she has deep knowledge to share, like a spring that keeps producing fresh water. A teacher might be a fount of patience, seeming to have an endless supply even when students ask the same question repeatedly.
The word originally referred to an actual fountain or spring where water flows up from the ground. Over time, it came to describe any generous source. A library could be a fount of information, or a friend might be a fount of creative ideas, always coming up with new suggestions for projects or games.
The word has an old-fashioned, somewhat poetic quality. You're more likely to encounter it in formal writing or literature than in everyday conversation. People might say “source” instead, but fount adds a sense of richness and plenty, suggesting not just any source but one that gives generously and doesn’t run dry.