Japanese vintage watch glossary

Condition grades

新品 shinpin

New and unused with original packaging. On a vintage watch, treat this as a claim of new old stock and verify it.

未使用品 mishiyō-hin

Unused but stored. Cosmetically new; gaskets and oils are still decades old, so a service is usually needed before wearing it.

極美品 goku-bihin

Excellent. Near-flawless appearance — and frequently the result of a recent polish, which is a reduction in value rather than a virtue. Ask for lug-thickness photographs.

美品 bihin

Very good. Light wear consistent with age, nothing significant.

良品 / 中古美品 ryōhin / chūko-bihin

Good used condition. Visible wear, honest example.

訳あり wake-ari

"There is a reason." A fault is acknowledged but often not specified. Always ask what it is before bidding.

現状渡し genjō-watashi

Sold as-is, no warranty of function, no returns. Common at pawnshops and estate sales.

ジャンク janku

Junk — for parts or restoration. Sometimes exactly what a restorer wants, and priced accordingly.

Function and service

動作確認済 dōsa kakunin-zumi

Operation confirmed: it runs. Says nothing about accuracy, amplitude, or water resistance.

オーバーホール済 ōbāhōru-zumi

Overhauled. By whom, when, and with which parts? Ask for the invoice — an unqualified claim is worth little.

日差 nissa

Daily rate in seconds gained or lost, usually measured by the seller in a single position. Treat as indicative only.

精度 seido

Accuracy. Often quoted with 日差 as a range.

要オーバーホール yō ōbāhōru

Service required. An honest and useful disclosure — budget JPY 40,000 upward depending on calibre.

止まる / 不動 tomaru / fudō

Stops, or does not run at all. With a rare reference this can still be worth buying; with a common one it rarely is.

Parts and originality

文字盤 mojiban

The dial. 文字盤リダン means it has been refinished.

リダン ridan

Redial — refinished by a third party. Typically a 30–50% reduction against an original dial, and frequently undisclosed.

純正 junsei

Genuine factory part, as opposed to aftermarket.

社外品 shagai-hin

Aftermarket part. Most often the crystal, crown or bracelet.

針 hari

The hands. Check that hand lume matches dial lume in colour and texture.

風防 fūbō

The crystal. A replaced crystal is normal and rarely affects value; a wrong-profile crystal changes how the watch looks entirely.

竜頭 ryūzu

The crown. Signed crowns are commonly replaced during service; an unsigned crown on a signed model is a small red flag.

蓄光 chikkō

Lume. Even, matching ageing across dial and hands is one of the strongest signs a watch has been left alone.

未研磨 miken-ma

Unpolished. The most valuable claim in a listing, and the one most loosely made. Verified only by measuring lugs and photographing facets.

磨き済 migaki-zumi

Polished. Metal has been removed; edges are softened permanently.

傷 / 打痕 kizu / dakon

Scratch / dent. Qualified as 小傷 (small) or 目立つ (noticeable).

保証書 hoshōsho

Original guarantee certificate. Dated and retailer-stamped, it can confirm both period and market.

箱付き hako-tsuki

With box. 内箱 inner box, 外箱 outer box. Full sets carry a real premium in Japan.

Market and trade

古物商 kobutsu-shō

A dealer licensed under Japan's Antique Dealings Act to trade second-hand goods. Legally required to deal used watches in Japan — worth checking that whoever you buy through holds one.

委託 itaku

Consignment. The shop is selling on an owner's behalf, which usually means less flexibility on price.

並行輸入 heikō yunyū

Parallel import — genuine goods outside official distribution, so no domestic manufacturer warranty.

質屋 shichiya

Pawnshop. In Japan a serious source of vintage watches, with stock that often never reaches the internet.

ヤフオク Yahuoku

Yahoo Auctions Japan, the largest domestic auction platform. Japanese addresses and payment only, which is why agents exist.

Collector vocabulary

Zaratsu polishing

A tin-plate lapping technique Seiko uses to create distortion-free flat mirror surfaces. Ordinary polishing destroys it, and restoring it properly is specialist, expensive work.

Suwa / Daini

Seiko's two competing factories, marked on dials and case-backs. Which one built a given reference affects desirability and price.

Service dial

A genuine factory dial supplied as a spare in a later period. Authentic, but not the dial the watch left the factory with — between original and redial in value.

Franken

A watch assembled from parts of different watches or periods. Fine if disclosed and priced accordingly; dishonest when sold as original.

NOS — new old stock

Unsold, unworn period stock, often from a closed retailer, sometimes still with hang tags.

JDM — Japanese domestic market

A model, dial or variant sold only through Japanese retailers and never officially exported.

Radium lume

Radioluminescent paint on pre-1960s dials. Harmless in a sealed watch, but some couriers restrict carriage, so it must be disclosed.

DAP — Delivered At Place formerly DDU

Shipping terms where the buyer pays import duty, VAT or GST and brokerage on arrival. DDU (Delivered Duty Unpaid) was dropped from Incoterms in 2010; sellers still use it and mean the same thing. See shipping and import.

Page last reviewed 8 September 2026. Missing a term? Send it to us and we will add it.