One might suggest that it is reaching orgasm by means other than penetrative sex so oral sex would qualify , another would say it is obtaining sexual pleasure by using hands or toys so orgasm isn't necessarily achieved - it can be sexual activity leading to intercourse , by yet another it is solitary sexual pleasure so here one person cannot 'masturbate' another - that would be petting or foreplay.
Thank you for your very detailed and fair response.
I remember lying and saying I was 14.