wellspring

From Middle English wellespring, from Old English wiellspring, wiellġespring (“spring, fount, fountain”), corresponding to well +‎ spring. More at well, spring.

• (General American) IPA^(key): /ˈwɛlsprɪŋ/

wellspring (plural wellsprings)

1. The source of water for a stream, spring or well; a fountainhead; a wellhead.
2. (figurative) A perennial source of anything; a fountainhead of supply or emanation; resource.
   • 2020 September 28, Alex McLevy, “Marilynne Robinson finds transcendence in the stunning, soul-searching Jack”, in The A.V. Club‎:

     We’re so often taught to simply believe in ourselves—to trust our instincts—that to see a narrative in which second-guessing oneself and refusing one’s deepest impulses is a potential wellspring of charity and good is, in itself, noteworthy.