Compound term: sport fishing.
Urheilu is a noun that means ”athletics” or ”sport” in general. It is often seen as a modifier in compound terms like urheiluvälineet (”sporting goods”), urheiluauto (”sports car”), urheiluvaatteet (”sportswear”), etc.
Kalastuksen is the genitive of kalastus, a noun which means ”fishing” in both the sport and commercial sense.
On our sign from the sport fishing shop, erikoisliike means ”specialty shop” or ”specialized shop.” It comes from erikois- (“special”) + liike (“shop, business, retailer”). Erikois- is the stem of the adjective erikoinen, and just the stem is often added to the main word instead of the full adjective.
Kalastin is first person past tense form of kalastaa, a verb that means ”to fish.”