tim·ber 
(tĭmbər)
(tĭmbər)n.
1.
a. Trees or wooded land considered as a source of wood.
b. Wood used as a building material; lumber.
2.
a. A dressed piece of wood, especially a beam in a structure.
b. Nautical A rib in a ship's frame.
3. A person considered to have qualities suited for a particular activity: That trainee is executive timber.
tr.v. tim·bered, tim·ber·ing, tim·bers
To support or frame with timbers: timber a mine shaft.
interj.
Used by one cutting down a tree to warn those around that the tree is about to fall.
[Middle English, from Old English, building, trees for building; see dem- in the Appendix of Indo-European roots.]