I like the Urban Dictionary definition.
Incel, aka "involuntarily celibate", a person (usually male) who has a horrible personality and treats women like sexual objects and thinks his lack of a sex life comes from being "ugly" when its really just his blatant sexism and terrible attitude. incels have little to no self awareness; even when they see other "ugly" men with girlfriends, they consider these men to be tricksters who have somehow beat the system and can get women despite being cursed with unattractiveness (in other words, theyre respectful to women and women are attracted to their personalities, but incels cant comprehend such a phenomenon). they believe that women owe them sex, and many of the more extreme incels like to spend time in incel communities on the internet coming up with ways to make women have sex with them (often involving genocide of people of color, genocide of "Chads" (men who have sex), taking rights away from women, raping them, having sex with women's dead bodies, and other horrid, disgusting things. they cant understand that that is PRECISELY why women want nothing to do with them).
"a person (usually male) who has a horrible personality and treats women like sexual objects"
hang on if these guys aren't getting laid, how can they treat women like sexual objects?
"theyre respectful to women and women are attracted to their personalities,"
i take issue with this to some extent, i've known guys including myself on certain occasions i suppose who women were attracted to despite not being respectful
furthermore i've known guys who wouldn't dare do anything to offend a woman, who women didn't regard even a slight bit as relationship options
i don't think that its a good idea to tell men that being respectful to women automatically makes them attracted to a man because for one thing its not true and secondly it breeds the same entitlement you seem to be criticing these "incels" of
men need to understand that just like men,, women are attracted to physical characteristics, obviously some cannot be adjusted such as height but physical fitness, hygiene etc can be improved
but i get the idea, sounds like guys bitter about not being successful with women, which i think could be a good thing if channeled into self improvement not self pity