say it: SIK-uh-ning
sickening is an adjective meaning "causing or able to cause nausea". It carries one recorded sense.
causing or able to cause nausea
“a nauseating smell”
“nauseous offal”
“a sickening stench”
Definitions, synonyms and semantic relations for sickening 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.