delight, joy
歡 centers on a lively, expressive feeling of delight and joy, often shared or outwardly shown.
歡 combines 雚 (a type of bird, possibly contributing sound) with 欠 (open mouth, expressing emotion), suggesting a joyful outcry. The modern Japanese simplified form is 歓.
The left side 雚 looks like a bird with a crest, and the right side 欠 is a person with an open mouth. Imagine a bird singing joyfully, making a person smile with delight.
For カン, picture a can of joy: opening a can releases a burst of delight, and the sound 'can' cues カン.