Board
Plank, Slab, Plate
noun
The kanji and the word are exactly the same. That means they share meanings as well.
板 generally refers to something thin, flat, and solid, like a board, plank, slab, or plate. In some contexts, it can also refer to stock market boards that display trading prices, or bulletin boards used for posting messages in online forums.
Since this word is made up of a single kanji, it uses the kun'yomi reading. You did not learn this reading, so here's a mnemonic to help you:
Who can make good use of various boards? An avid eater (いた)! If you’re an avid eater, you’ll need lots of (cutting) boards to prepare all the delicious food you’re going to eat. This makes boards and eaters the perfect match.
ノコギリで木の板を切りました。
I cut a wooden plank with a saw.
このプラスチックの板、何に使うの？
What are you going to use this plastic board for?
この置物に合う大理石の板をさがしています。
I'm looking for a marble board that matches this ornament.
2chの野球板に書き込みをしたんですが、板違いだと言われてしまいました。
I posted some comments on a forum about baseball on 2chan, but I was told it was the wrong board.