Are anglers and fishermen the same thing? It depends on who you ask, but technically the answer is no; they are not the same.
All angling is fishing, but not all fishing is angling. Dictionary.com defines the noun “angler” as “a person who fishes with a hook and a line.” Anglers are distinguished by the fact that they fish with metal hooks and fish recreationally and often release the fish they catch. The Old English term “angle” defines a modern-day fishhook, and the act of fishing with an angle is called, you guessed it, angling. Angling is a technique that is only used with a rod, reel, and a hook- no other equipment. This makes sense as to why the deep-sea creature is called an Anglerfish since the species has a dorsal spine that protrudes above its mouth and looks like a fishing pole. However, the species was named after the angler, not the other way around.
On the other hand, Dictionary.com defines the noun “fisherman” as “a person who fishes, whether for profit or pleasure.”
So, while the words are basically interchangeable, the minor difference is that “fisherman/fishing” can mean commercial or recreational fishing with nets, bow fishing, traps, hook, line, and techniques and methods in all sorts of fashion. While angling/angler are specific to using hook and line.