say it: LUHM-bur-ing
lumbering is a noun and adjective meaning "the trade of cutting or preparing or selling timber". It carries 2 recorded senses.
the trade of cutting or preparing or selling timber
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for lumbering come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.