take pleasure in, play instrument
翫 centers on deriving enjoyment from something, especially through hands-on engagement: taking pleasure in an activity or playing a musical instrument.
翫 combines 習 (learn, practice) with 元 (origin, source), suggesting the idea of becoming familiar with something through repeated practice and taking pleasure in it. The exact historical development is uncertain.
The left side 習 suggests repeated practice, and the right side 元 hints at the source of enjoyment. Picture someone practicing a musical instrument over and over until they can play it with pure pleasure.
For ガン, imagine a person playing a musical instrument with such passion that they become a 'gan' (as in 'gun' but with a short 'a') at it: gan -> ガン, and they take great pleasure in their skill.