Merriam-Webster's Collegiate® Dictionary, 11th Edition
LUMBER
I. intransitive verb (lumbered; lumbering)
Etymology: Middle English lomeren
Date: 14th century
to move ponderously, rumble ,
II. noun
Etymology: perhaps from Lombard; from the use of pawnshops as storehouses of disused property
Date: 1552
surplus or disused articles (as furniture) that are stored away,
2. timber or logs especially when dressed for use, any of various structural materials prepared in a form similar to lumber, lumber adjective
III. verb (lumbered; lumbering)
Date: 1642
transitive verb to clutter with or as if with lumber ; encumber , to heap together in disorder, to log and saw the timber of, intransitive verb to cut logs for lumber, to saw logs into lumber for the market, lumberer noun