'Bear' is a gay slang term used to categorize a particular type of homosexual male based on his appearance, and by extension, his identity within the community. Here's how to identify one.
When observing the males around you, the first thing to pay attention to is age. Bears are generally older men who are at least thirty years old (often much older).
Step2
Observe their physical appearance. Bears are more heavyset and/or muscular than the average man - but not lazilly obese. Often-times there is a pronounced amount of body hair. Lack of excessive hair does not necessarily rule out categorization as 'bear,' but it is an important feature.
Step3
Next, study the subject's demeanor. Bears are generally butch in appearance, action, and attitude, even going so far as to display a macho disapproval of the feminine.
Step4
Observe the subject's friends, if any are nearby. If the subject is associating with other males who possess similar bear qualities as described above, then the subject is very likely a bear. If the subject is associating with younger and pointedly smooth, innocent or feminine males, observe the subject's action and demeanor for signs of sexual aggression. This is also indication that the subject is a bear.
Step5
Take note of the subject's clothing and other signifiers. The wearing of leather, especially fetish or motorcycling gear, increases both the subject's masculinity and ability to label him as a bear. Other things to take note of are the presence of a shaved head, excessive facial hair, tattoos, and macho-looking accessories, such as chains.