Fetching details from the dictionary...
pastime; hobby; favorite amusement
dissipation; debauchery; loose living; prodigality; indulging in alcohol, women, gambling, etc.; profligacy
「道楽」 has another reading with different meanings.
彼は釣りで道楽している。
He indulges in fishing as a pastime.
父は道楽にたくさんお金を使う。
My father spends a lot of money on his hobbies.
彼の唯一の道楽は古い切手を集めることだ。
His only pastime is collecting old stamps.