Definitions
1.NounA person in postindustrial society who combines the economic roles of producer and consumer.
2.AdjectiveTargeting serious, enthusiastic consumers, incorporating professional features but often modified for non-professional use.
3.AdjectiveHigh-end.
4.NounA serious, enthusiastic consumer: not professional (earning money), but of similar interest and skills to a (generally lower-level) professional, or aspiring to that.