Read the dictionary definition of birch. All definitions for this word.
1. a switch consisting of a twig or a bundle of twigs from a birch tree; used to hit people as punishment
1. my father never spared the birch
2. any betulaceous tree or shrub of the genus Betula having a thin peeling bark
3. hard close-grained wood of any of various birch trees; used especially in furniture and interior finishes and plywood
4. whip with a birch twig
5. consisting of or made of wood of the birch tree
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Merriam-Webster definition of birch