1950s; earliest use found in The Chicago Defender. Origin uncertain; perhaps from boon + coon, perhaps influenced by boon companion and perhaps also by boo koo, variant of bookoo beaucoup adjectiveadverb.
Definition of boon coon in US English:
boon coon
(also boon koon)
nounˈbuːn kuːn
US slang
A close friend.
Origin
1950s; earliest use found in The Chicago Defender. Origin uncertain; perhaps from boon + coon, perhaps influenced by boon companion and perhaps also by boo koo, variant of bookoo beaucoup [adjective, adverb].