single-minded absorption; complete concentration on one practice
A yojijukugo from Buddhist practice, referring to total immersion in a single act, especially prayer or meditation. Often used in religious or spiritual contexts, but can be extended to any deep, focused dedication to one thing.
See also: 念仏三昧
He is engaged in copying sutras in a state of single-minded absorption.
He deepened his practice from nembutsu absorption to one-practice absorption.