By my definition, a collector has a specific theme to the items he collects (not necessarily just guns). For example, collecting all styles and calibers of Winchester Model 70 rifles. An accumulator, by contrast, doesn't necessarily have a particular theme, he just buys whatever strikes him as being interesting regardless. Many years ago I was the former (specifically US-made .32 and .380 pocket pistols and late 19th-early 20th century US-made regulator wall clocks - Ansonia, Gilbert, Ingraham, Seth Thomas, etc.), but have been for a long time much more the latter. I have some of about everything.