say it: LAHY-twayt
lightweight is a noun and adjective meaning "a professional boxer who weighs between 131 and 135 pounds". It carries 6 recorded senses.
a professional boxer who weighs between 131 and 135 pounds
someone who is unimportant but cheeky and presumptuous
an amateur boxer who weighs no more than 132 pounds
a wrestler who weighs 139-154 pounds
weighing relatively little compared with another item or object of similar use
“a lightweight fabric”
“lightweight wood”
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 lightweight 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.