Woman- a generic term, appropriate in most circumstances, but there are some circumstances where it is better to use lady, which is more formal and polite
Lady- more formal and polite; more romantic, if you are using it in a romantic context
Girl- very informal, used only when referring to woman your age or younger. Many people refer to their close friends as "girls." Even my mother, who is 50, occasionally calls her 50-year-old friends "girl," but I would never call them girl because they are older than me.
If you are a man, you should probably not refer to a woman as a "girl," unless you are gay or she is young enough to be your granddaughter (even then you might want to be careful). If a man refers to a woman as a "girl," most people will assume that either (a) he is gay or (b) he is being rude and talking down to her.
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Your Aspie score: 120 of 200 ; Your neurotypical (non-autistic) score: 90 of 200
You seem to have both Aspie and neurotypical traits
Self-DX: Extreme Introvert, possibly with ADHD-Primarily Inattentive; Official DX: Generalized Anxiety Disorder