Extremely angry or furious (often used as in 'カンカンに怒る').
彼は約束を忘れられてカンカンに怒った。
He was furious when the promise was forgotten.
上司に叱られて部長はカンカンだった。
After being scolded, the manager was enraged.
そんなことをするなんて母がカンカンになるよ。
If you do that, Mom will be furious.
Blazing or fiercely (as in strong sunlight); used in expressions like 'カンカン照り' (scorching sun).
今日はカンカン照りで外に出るのもつらい。
Today the sun is blazing; it's hard even to go outside.
運動場は昼過ぎにはカンカンに日が当たっていた。
By early afternoon the sports ground was scorched by the sun.
Describing something glowing red-hot or burning brightly (an onomatopoeic use; somewhat old-fashioned).
かまどの炭がカンカンと燃えて、料理がよく火が通った。
The charcoal in the stove burned brightly, and the food cooked well.
A clanging sound made when hard objects strike each other (onomatopoeic for a 'clang').
鍋が棚にぶつかってカンカンと音を立てた。
A pot hit the shelf and clanged loudly.
彼の鍵がポケットの中でカンカン鳴っていた。
His keys were jangling in his pocket.