How to say "slab" in Japanese

Choosing the right word

平板へいばんCommon
nounCovers 'slab' as a flat board — the word itself means 'flat board', and slat and plane table are among its other senses. Use it to describe a slab as a flat, board-like piece.
板いたJLPT N3approx.Common
nounCovers 'slab' as a flat piece of material; its other senses include sheet of metal, plate of glass, and pane. Use it when you mean the slab as a sheet or plate.
この鉄てつの板いたはすずでメッキしてある。↗
This iron sheet is coated with tin.

Both words cover 'slab': 板 names a flat piece of material — a metal sheet, a glass plate, a pane — while 平板 means 'flat board', for a slab you describe as a flat, board-like piece.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

平板へいばんflat board
スラブslab
鋳片ちゅうへんslab (e.g. in metal casting, smelting, etc.)
鋼片こうへん(steel) billet
板いたsheet (of metal)
タブレットtablet

JLPT vocabulary levels are community estimates, not official (no official lists have been published since the 2010 revision).

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