say it: FLAT-bed
flatbed is a noun meaning "freight car without permanent sides or roof". It carries 2 recorded senses.
freight car without permanent sides or roof
an open truck bed or trailer with no sides; used to carry large heavy objects
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 flatbed 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.