say it: AHR-noh
arno is a noun meaning "a river in central Italy rising in the Apennines and flowing through Florence and Pisa to the Ligurian Sea". It carries one recorded sense.
a river in central Italy rising in the Apennines and flowing through Florence and Pisa to the Ligurian Sea
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 arno 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.