closely knit is an adjective meaning "held together as by social or cultural ties". It carries one recorded sense.
held together as by social or cultural ties
“a close-knit family”
“close-knit little villages”
“the group was closely knit”
Definitions, synonyms and semantic relations for closely knit come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.