Based on the sources, Iban spiritual beliefs and rituals profoundly shape their language by creating a specialized vocabulary, a rich oral literature, and complex terms for the supernatural and the afterlife.

Specialized Ritual Vocabulary

The Iban language features a vast array of terms specifically dedicated to their spiritual practices, or gawai 1, 2.

• Spirit Mediums and Rituals: The term manang refers to spirit mediums, while specific words like piring describe ritual offerings 1, 3. One essential ingredient in these offerings is rendai, or puffed rice 3.
• Sacred Objects and Taboos: Rituals often center on the ranyai, a shrine erected in the gallery of a long-house that is believed to be the abode of gods during ceremonies 2. These areas are often surrounded by pemali, or taboos 2.
• Specific Ritual Concepts: The language includes terms for distinct ritual actions, such as tampok, which is the act of keeping a vigil in a solitary place to meet gods or spirits to seek favor 4.

The Vocabulary of the Supernatural

Iban language is shaped by a complex mythology populated by hundreds of gods, "culture heroes," and various spirits 1.

• Divine Beings: A cardinal figure in Iban thought is Sempandai, the god of creation 1.
• Familiar and Malevolent Spirits: Successful men are believed to have antu nulong (familiar spirits) like the nabau (serpent spirit) or antu remaung (tiger spirit) 4. Conversely, the language accounts for malevolent spirits such as antu buyo, male spirits blamed for miscarriages, leading to the specific phrase bebunoh buyo (to kill the evil spirit) 2, 4. Another spirit, the antu koklir, is the vengeful soul of a woman who died in childbirth 2.

Concepts of the Soul and Afterlife

Spiritual beliefs regarding death have created a nuanced terminology for the soul's journey:

• Samengat: The soul or "soul-counterpart" that all objects possess and which is transported to the Afterworld 5.
• Sabayan: The Afterworld, which is viewed as a replica of this world 5.
• Baiya: A collective term for the clothes, ornaments, and tools a person is equipped with in their grave for use in the Afterworld 5.
• Rapoh: A specific term and custom for property belonging to someone who died abroad; these items are buried in a "grave at home" so the soul can use them in the next world 5.

Poetic Language and Oral Literature

The Iban possess a massive "oral literature" that uses intricately patterned and highly poetic language to communicate with the divine 6.

• Timang: These are chanted invocations used to summon gods. Described as the "scriptures" of the Iban, they are performed in a polyphonic style by a lemambang (chanter) and chorus, often lasting several days 6.
• Ritual Laments: Other specialized linguistic forms include sabak (laments for death rituals), naku (chants associated with head-hunting), and pelian (language used by spirit mediums) 6.

In summary, the Iban language is not merely a tool for mundane communication but is a "living force" deeply intertwined with their mythology and the "esoteric concepts" of their spiritual life 1, 6.