say it: PAYN-stay-king-lee
painstakingly is an adverb meaning "in a fastidious and painstaking manner". It carries one recorded sense.
in a fastidious and painstaking manner
“it is almost a waste of time painstakingly to learn the routines of selling”
Definitions, synonyms and semantic relations for painstakingly 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.