triratna [tiratana] three jewels, three gems. Triratna stands for the three venerable things for the followers of Buddhism. They are the Buddha, the Law discovered, realised and proclaimed by him (dharma), and the congregation, that is, the Order of the Holy disciples (saṅgha).

Buddhānusmṛti - A Glossary of Buddhist Terms

Aṭṭhasālinī. III. 484. Bodhicaryāvatāra. II. 22. Meditation on Buddha Amitāyus. III. 196.