Shikoku — the one true spelling, and the forms that fail it
A letter to a colleague, 31 July 2026 — on the name Shikoku, and on the forms that keep failing it.
Your note said, roughly: surely the marks are a nicety. Permit me to use Shikoku to show they are not.
First, the attestation. The name is attested as 四国, on the evidence Kūkai, Sango Shiiki (797) and Shōrai Mokuroku (806). and Statler, Oliver, Japanese Pilgrimage (Morrow, 1983). set down. On the evidence, it means "Four provinces". The canonical transliteration is Shikoku.
Say it aloud as the sources heard it: 'SHEE-koh-koo' — three crisp syllables. The marks are what carry that sound to a reader who has never heard it spoken.
On the plain form — and I want to be precise, because you pushed on this. The plain form shikoku differs from the canonical Shikoku only by convention of display — case, not content. It is acceptable everywhere: in legacy systems, in plain-text citation, in the DNS itself. What is not acceptable is what follows in the register: respellings that change the letters, not just their case.
One more thing, because it always surprises: the name did not stay home. Shikoku's religious landscape is layered rather than replaced. Buddhist temples and Shinto shrines share precincts along the henro, and the island's kami — the mountain powers of Ishizuchi, the sea deities of the whirlpool coast — are read through the honji-suijaku logic as local manifestations of buddhas and bodhisattvas.
And it never stopped working. The Shikoku Henro remains one of Japan's most important pilgrimages, walked by tens of thousands each year — on foot, by bus, in section over a lifetime — and studied worldwide as a model of living religious practice (Statler, Japanese Pilgrimage, 1983; Reader & Tanabe, Practically Religious, 1998). The island's rural culture, its udon, its vine bridges and thatched Iya villages are celebrated as the 'hidden Japan' of slow travel.
The Convention's Own History
Every tradition in this register has its own scholarly transliteration standard, built by its own specialists over decades or centuries, and the register follows each on its own terms: Hepburn with macrons — ō and ū marked, never collapsed to o/u or rewritten ou. The principle that unifies them is the one the whole project stands on: a name is evidence, and evidence is not negotiable — not for keyboards, not for convenience, not for anyone.
Where Protocol Meets Practice
The technical answer is simple: the canonical marks are legal IDNA 2008 characters, encoded as punycode under `xn--`. The practical answer is messier: legal does not mean stocked (registrar inventory is partial), and stocked does not mean typeable (stacked diacritics defeat mobile keyboards).
So the register's rule is a hierarchy of attested forms — full restoration, circumflex, macron-only, attested variant, and finally plain ASCII for the systems that cannot carry marks. Every rung is defensible because every rung is attested. The forms this register rules against are not rungs; they are errors, and errors do not get rungs.
Write back when you have checked the sources; they are better company than I am.
— The Register
The Verdict
Shikoku is the canonical form: attested, checkable, and enforced across the temple, the lexicon, the cards, the APIs, and this register. The plain form shikoku shares that standing — the two are the same name in every system. The false forms above are documented so that no reader has to take the temple's word on faith — the violations are stated, the sources are named, and the register stands open to challenge on every line.
The temple of Shikoku stands at /shikoku/.
The docket for this ruling: no false forms on the docket; no contested forms attested; the attestation rests on 4 cited sources — Kūkai, Sango Shiiki (797) and Shōrai Mokuroku (806)., Statler, Oliver, Japanese Pilgrimage (Morrow, 1983)., Reader, Ian, and George J. Tanabe Jr., Practically Religious: Worldly Benefits and the Common Religion of Japan (University of Hawai'i Press, 1998)..
The Register Continues
The register holds 548 entries like this one — each temple with its own ruling. Read the temple's founding dispatch for the story, its Restoration File for the philology, its Resonance File for the industries, or the whole archive end to end.
Continue the register — previous entry: Šāpšu (read it) · next entry: Śiva (read it).
The Canonical Register is written from the same canonical record as the lexicon itself. If a false form is missing from this page, it is because the evidence does not support calling it false — or because we have not seen it yet. Show us, with a citation, and the register will answer.