say it: TAK-sing
taxing is an adjective meaning "not easily borne; wearing". It carries one recorded sense.
not easily borne; wearing
“the burdensome task of preparing the income tax return”
“my duties weren't onerous; I only had to greet the guests”
“a taxing schedule”
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 taxing 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.