I don't really know if similar question or concerns has been raised before, we often say that we are gamblers but does it mean that anyone who gambles once or twice is a gambler? If no, how long could someone be classified as a gambler or what games that are to be classified as someone gambling.
I think a gambler can also be called as risk-taker, so it isn't only limited on playing a gambling game. If about gambling, a duration of playing time won't matter.
A person that plays gambling for the first time, can immediately be called as a gambler. There are people which profession is a literal gambler. You know, people that are playing for big games regularly and even had some sponsorships.
Even a normal person can also be classified as one, if they don't have a main job and treats gambling as their main source of income or at least one of it because they can also have other business like a sari-sari store. Just want to share that on the e-wallet I'm using, they classify me as a gambler when I check on my profile. It may be because most of my transactions are from an online casino, lol but I do have my main job.