What does „birch“ mean?

This is what Monolingual dictionaries say:
The noun „birch“ has 3 senses:
1. birch- hard close grained wood of any of various birch trees; used especially in furniture and interior finishes and ply wood.

2. birch , birch tree- any betulaceous tree or shrub of the genus betula having a thin peeling bark.

3. birch, birch rod- bundle of birch twigs used to hit people as punishment.

The verb “birch” has one senses .
1. birch- whip with a birch twig.

The adjective “birch” has one senses .
1. birch , birchen, birken- consisting of or made of wood of the birch tree.

http://www.word2word.com/english.html

There are many different species of birch trees. They can be divided into two kinds, the white bark birches and the dark bark birches. The native white bark birches are: European White Birch, Silver Birch ( Betula pendula) .
Paper Birch Canoe Birch (Betula papyrifera) .
Grey Birch, Poplar Birch (Betula populitolia)

The native dark bark birches are:
Yellow Bark Birch (Betula lutea)
Sweet Birch, Cherry Birch ( Betula lenta)
Red Birch, Black Birch, River Birch (Betula nigra)
Water Birch ( Betula occiolentalis)
Ashe’s Birch ( Betula uber)

http://www.hortsource.com/birch_trees.htm
http://www.2020site.com/trees/birch.html
http://www.thewoodbox.com/data/wood/birconto.htm
http://www.domtar.com/arbre/english/p-boulj.htm

To the Celts and many other people, certain trees believed to the sacred. One of those
trees was the birch tree.

http://geocities.yahoo.com/

The Celts divided their year into tree months. The first tree in the Celtic calendar was
Birch (Beth) – from December 24 – January 20 .

Poet Robert Frost wrote a nice poem called “ Birches “

http://quotations.about.com/cs/poemlyrics/a/Birches.htm

The word "birch" has been used as a family name in the English language: actors, scientists, etc. like John Birch, Edna Birch, Thora Birch.

http://thora.org/navframe.html
http://emmerdale.org/emmerdale/profiles/edna.htm
http://college.hmco.com/history/readerscomp/rcah/html/ah_047800_johnbirchsoc.htm

Compiled by: Karl-Jürgen Kivi, Jane Lohu, Kerttu Pakkonen
Instructed by: Tiiu Kitsemets