from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A smooth hard panel, usually green or black, for writing on with chalk; a blackboard.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A slate board for writing on with chalk; a predecessor to a whiteboard.
from the GNU version of the Collaborative International Dictionary of English
- n. a dark sheet of slate used as a surface for writing on, with chalk.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. sheet of slate; for writing with chalk
chalk + board (Wiktionary)