connoisseur; devotee; enthusiast
Refers to someone deeply knowledgeable and passionate about a particular hobby or interest, often with refined taste. Less common than 愛好家 (あいこうか) or マニア, but carries a similar nuance of expertise.
He is a wine connoisseur and knows brands from all over the world.
趣味家の集まりで骨董品について語り合った。
We talked about antiques at a gathering of enthusiasts.
Compound of 趣味 (しゅみ, 'hobby; taste') and 家 (か, 'person; expert'). The exact historical derivation is uncertain, but the word follows a common pattern for forming agent nouns in Japanese.