say it: BUHT-uhn-hohl
buttonhole is a noun and verb meaning "a hole through which buttons are pushed". It carries 2 recorded senses.
a hole through which buttons are pushed
detain in conversation by or as if by holding on to the outer garments of; as for political or economic favors
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 buttonhole 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.