瑜伽師地論略纂 8.111

8.111

論云「阿那波那念」者，阿那名持來，波那名持去。持來者入息，持去者出息。亦名持息來、持息去也。

Regarding the treatise mentioning "ānāpānasmṛti": *āna* means bringing in, and *apāna* means taking away. Bringing in is the inhalation, and taking away is the exhalation. It is also called bringing the breath in and taking the breath away.