say it: kuhm-PA-nyuhn-ship
companionship is a noun meaning "the state of being with someone". It carries one recorded sense.
the state of being with someone
“he missed their company”
“he enjoyed the society of his friends”
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 companionship 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.