Meaning
鉄 means iron — the heavy, dark metal that Japan built its railways on. It also carries a figurative sense of something unbreakable or absolute, much like the English expressions "iron will" or "iron rule." Both uses are common in everyday Japanese.
The character has two parts. On the left is the radical 金 (きん), which marks any kanji related to metal. On the right is a more complex component that evolved through centuries of Chinese script history. The full character has 13 strokes and is taught in Grade 3 of Japanese elementary school — most children learn it around age 8–9.
Chinese simplified the character to 铁 (tiě); Japanese kept the older form 鉄. The Hán-Việt reading is THIẾT, which appears in Vietnamese words like thiết bị (equipment) and thiết kế (design/engineering). Note that the Vietnamese word for the element iron — sắt — is native Vietnamese and unrelated to THIẾT.
Spotting the 金 radical is one of the most practical skills at the intermediate kanji level. It marks every major metal: 金 (gold), 銀 (silver), 銅 (copper), 鋼 (steel), 鉄 (iron), 鉛 (lead).
Readings
On'yomi (音読み) — Chinese-derived readings
テツ is the on'yomi and the reading you'll use nearly every time 鉄 appears in a compound. It entered Japanese from Middle Chinese alongside vocabulary for metalworking and construction. In isolated kanji readings, テツ also works — but compounds are far more common in practice.
Pay attention to a common sound change: when テツ precedes certain consonants, the final tsu becomes a double consonant (っ). So 鉄橋 is pronounced てっきょう, not てつきょう. This pattern — called sokuon assimilation — also applies to 鉄板 (てっぱん), 鉄砲 (てっぽう), and 鉄鋼 (てっこう).
Example compounds using テツ:
- 鉄道 (tetsudou) — railway, railroad
- 地下鉄 (chikatetsu) — subway, underground train
- 鉄鋼 (tekkou) — steel
Kun'yomi (訓読み) — Native Japanese readings
The kun'yomi くろがね literally means "black metal" — an old, poetic Japanese name for iron. It has no place in modern everyday speech. You'll encounter it mainly in classical literature, historical texts, or as a personal or place name. The word captures how ancient Japanese perceived iron: a dark, weighty metal, nothing like the gleam of gold or silver.
- 鉄 (kurogane) — iron (literary/classical usage)
Common Words & Compounds
Iron and railways run through Japanese vocabulary in ways that reflect the country's rail culture and industrial past. These are the compounds worth knowing first.
Transportation & Infrastructure
- 鉄道 (tetsudou) — railway, railroad; the backbone of Japan's transport network
- 地下鉄 (chikatetsu) — subway, underground rail system
- 鉄橋 (tekkyou) — iron bridge
- 私鉄 (shitetsu) — private railway (as opposed to national or public lines)
- 路面電車 (romen densha) — tram, streetcar
Materials & Objects
- 鉄板 (teppan) — iron plate; metaphorically, something rock-solid or guaranteed
- 鉄棒 (tetsubou) — iron bar; also the gymnastics horizontal bar
- 鉄砲 (teppou) — gun, firearm (literally "iron cannon")
- 鋼鉄 (koutetsu) — steel
- 鉄製 (tetsusei) — made of iron
Figurative & Idiomatic Usage
- 鉄則 (tessoku) — iron rule; an absolute principle that cannot be broken
- 鉄拳 (tekken) — iron fist; a powerful punch, or strictly enforced discipline
- 鉄人 (tetsujin) — iron man; someone with extraordinary endurance or strength
- 鉄壁 (teppeki) — iron wall; an impenetrable defense
Example Sentences
この橋は鉄で作られています。
Kono hashi wa tetsu de tsukurarete imasu.
This bridge is made of iron.
地下鉄で駅まで行きます。
Chikatetsu de eki made ikimasu.
I take the subway to the station.
日本の鉄道はとても正確です。
Nihon no tetsudou wa totemo seikaku desu.
Japan's railways are remarkably punctual.
鉄板で野菜を焼きました。
Teppan de yasai wo yakimashita.
I grilled vegetables on an iron plate.
彼は鉄のような意志を持っています。
Kare wa tetsu no you na ishi wo motte imasu.
He has a will of iron.
鉄棒の練習は毎日しています。
Tetsubou no renshuu wa mainichi shite imasu.
I practice on the horizontal bar every day.
この会社の鉄則は時間を守ることだ。
Kono kaisha no tessoku wa jikan wo mamoru koto da.
This company's iron rule is to be on time.
鋼鉄は鉄よりも硬い素材です。
Koutetsu wa tetsu yori mo katai sozai desu.
Steel is harder than iron.
私鉄と地下鉄、どちらが便利ですか？
Shitetsu to chikatetsu, dochira ga benri desu ka?
Which is more convenient — the private railway or the subway?
Memory Tip
Start with the left side: 金 tells you this is a metal kanji. From there, anchor the character to 地下鉄 — say it aloud: chi-ka-te-tsu. That final テツ is your reading, attached to the most iconic compound in the set. Japan runs on iron rails; let the subway be your hook.
The sokuon pattern is worth drilling separately. When you see 鉄 before a voiceless consonant, the tsu disappears into a double stop: 鉄板 → てっぱん, 鉄砲 → てっぽう, 鉄橋 → てっきょう. Three words, one rule.
Vietnamese learners: THIẾT appears in thiết kế (design) and thiết bị (equipment) — iron as the foundation of engineering. Chinese learners will find 铁 (tiě) almost identical in meaning, just simplified in form.