Meaning
胎 means womb, uterus, and — by extension — fetus or embryo. It covers both the organ where a child develops before birth and the developing life inside it. The character appears in medical texts, prenatal literature, and writing where the womb serves as a metaphor for origin and new beginnings.
The kanji has two components. On the left is 月 (にくづき, nikuzuki) — not the moon, but the flesh radical that marks body-part kanji: 腹 (belly), 腸 (intestines), 肌 (skin). On the right is 台 (dai/tai), the phonetic element that gives 胎 its タイ reading. Flesh encasing a structure — the character points directly to the body's inner chamber.
胎 has 9 strokes and appears on the Jōyō kanji list at Grade 8 (secondary school). It rarely surfaces in casual conversation but shows up in medical writing, news journalism, and literature.
Readings
On'yomi (音読み) — Chinese-derived readings
胎 has one on'yomi in modern Japanese:
タイ (tai) — derived from classical Chinese, this is the only reading used today. It appears almost exclusively in compound words (熟語, jukugo) rather than standing alone.
Key compounds using the タイ reading:
- 胎児 (taiji) — fetus; the developing human inside the womb
- 胎盤 (taiban) — placenta; the organ that nourishes the fetus
- 胎動 (taidou) — fetal movement; the kicks felt by a pregnant mother
- 母胎 (botai) — mother's womb; also used metaphorically for the source of something
- 受胎 (jutai) — conception; the moment of fertilization
Kun'yomi (訓読み) — Native Japanese readings
胎 has no kun'yomi in modern Japanese. All practical usage goes through the タイ reading — the compounds above are your entry points into this character.
Common Words & Compounds
All compounds below use the タイ reading across medical, biological, literary, and journalistic contexts.
Pregnancy and Development:
- 胎児 (taiji) — fetus; technically refers to the developing human from the eighth week onward, still inside the uterus
- 胎動 (taidou) — fetal movement; the sensation of a baby moving in the womb, typically felt from around 18–20 weeks
- 胎内 (tainai) — inside the womb; the uterine environment during gestation
- 懐胎 (kaitai) — pregnancy; a formal, literary term for carrying a child
- 受胎 (jutai) — conception; the act of becoming pregnant through fertilization
Medical and Anatomical Terms:
- 胎盤 (taiban) — placenta; the temporary organ providing nutrients and oxygen to the fetus throughout pregnancy
- 堕胎 (datai) — abortion; induced termination of pregnancy; used in formal medical and legal contexts
- 胎教 (taikyo) — prenatal education; the practice of exposing a fetus to music or language to encourage early development
Extended and Metaphorical Uses:
- 母胎 (botai) — in philosophical and literary writing, the birthplace or cradle of an idea, movement, or era — not just a physical womb
- 胎動 (taidou) — in journalism, the barely perceptible stirrings of political or social change. Writers reach for this word when something new is forming beneath the surface, not yet visible.
Example Sentences
胎児は母親の胎内でゆっくりと成長する。
Taiji wa hahaoya no tainai de yukkuri to seichou suru.
The fetus slowly grows inside the mother's womb.
妊娠5ヶ月になると、胎動を感じることができる。
Ninshin go kagetsu ni naru to, taidou wo kanjiru koto ga dekiru.
At five months of pregnancy, you can begin to feel the fetal movement.
胎盤は母親と赤ちゃんをつなぐ大切な臓器だ。
Taiban wa hahaoya to akachan wo tsunagu taisetsu na zouki da.
The placenta is an important organ that connects the mother and baby.
受胎から出産まで約40週間かかる。
Jutai kara shussan made yaku yonjuu shuukan kakaru.
It takes approximately 40 weeks from conception to birth.
胎教として、妊婦がクラシック音楽を聴く習慣がある。
Taikyo to shite, ninpu ga kurashikku ongaku wo kiku shukan ga aru.
Some pregnant women make a habit of listening to classical music as prenatal education.
母胎から生まれ落ちた瞬間、赤ちゃんは泣き声を上げた。
Botai kara umare ochita shunkan, akachan wa nakigoe wo ageta.
The moment the baby emerged from the womb, it let out a cry.
この小説は近代文学の母胎となった作品だ。
Kono shousetsu wa kindai bungaku no botai to natta sakuhin da.
This novel became the cradle of modern literature.
新しい時代の胎動を、誰もが感じ始めていた。
Atarashii jidai no taidou wo, dare mo ga kanji hajimete ita.
Everyone was beginning to sense the stirrings of a new era.
懐胎したばかりの彼女は、体の変化に驚いていた。
Kaitai shita bakari no kanojo wa, karada no henka ni odoroite ita.
She had just conceived and was taken aback by the changes in her body.
Memory Tip
Break 胎 into its two parts. Left: 月 — the flesh radical, found throughout body-part kanji. Right: 台 — a platform or stage. Picture a baby resting on a warm cushioned platform inside a body. That is precisely what a fetus does: it sits on a flesh-enclosed platform, safely held before birth.
For the sound, connect タイ (tai) to the English "tie" — the baby is tied to its mother through the umbilical cord. Flesh platform + tied to mother = 胎.