.^_^. I don't know where you are from but I'm a fluent English speaker, a native American-English speaker. I'd love to help. The answers you received are wrong because they do not address the fact that the male trying to pick up the girl was rude to her.
To "Snub" someone is to disregard, "turn your nose up at", them as if you are too good for them based on a superficial indication of status.
Ex: Celebrity VS Fan, Popular Girl VS LonerNerd, Rich Guy VS Poor girl, etc. So to say that she "snubbed him" would be a negative on her character. He was rude so he would have deserved the rejection, that means no snubbing on the girl's part. Especially when dealing with strangers. If we are dealing with people who are familiar with each other then snubbing would indicate a private quarrel that caused the two not to be speaking in public, when rightfully they should. Like a talented well known actress/musician getting snubbed at award shows due to internal conflicts behind the scenes.
To "blow him off" or "tune him out" both amount to ignoring his advance on her but neither are critical. You said you want something that indicates "to send someone as far as he can get to :)"
A pure slang for that kind of rejection is "to curve"
Example #1
Guy: Hey toots! What will it take for ya to dance with big daddy?!
Lady: A Cold day in hell. walks away
Friends: Ohhhh! She curved the heck out of him!
In order for her response to be considered a curve it's not about the insult itself but the delivery. A SWIFT, Direct, and FINAL response. Her tone of voice and facial expression is what cements the injury to his ego. Walking away leaves no chance for him to follow up, but even if she didn't walk away and just looked him in the eye, or looked past him pretending not to see him, it would be an ego bruising curve. He will look and feel like a fool, or at the very least know that he better find a new target. We also call this "shutting it down". The word "it" in this case alludes to the entire situation, but to be more direct you can use him/her instead.
Ex: Mike was trying to pick her up at the party yesterday but she just shut him down.
Ex: Mike was trying to pick her up at the party yesterday but she just curved him.
**Note: What makes the guy rude and worthy to be curved in this situation is him calling her "toots". It's demeaning. Coupled with him calling himself big daddy showing his inflated ego and undermining her presence.
Curving someone or shutting them down can also be more subtle or even comical. It simply means not to entertain their antics AT ALL. Among young people/teens even if you are interested in a person a lady will have to curve the guy she likes from time to time to stop situations from getting out of hand ;)
You can read a few examples from Urban Dictionary.
I'll post this example of curving through texts.
To ignore, avoid or sidestep someone's obvious expression of interest through flirting or any means of advance.
Person 1: "Hey baby I miss you"
Person 2: "Goodnight bruh"
hashtag: just got curved
curve
What would make that a curve is the fact Person 1 and Person 2 are not in a relationship so Person 1 is sweet talking by calling Person 2 baby. If person 2 is female her saying "bruh" is a comedic indicative that her response is deliberate and calling for him to "chill out" meaning stop. She's avoiding sweet talk because it usually leads to other things/feelings. If he does "chill" they will just move on to a different topic. So she would have curved his attempt to get mushy. If he continued by saying "No really I can't get your pretty face out of my mind" to cement her curve she will likely not respond after saying "Goodnight bruh" and they'll address it in person later. But his attempt to get mushy would have still been shut down be her direct and abrupt response that did not reciprocate his feelings.
SORRY TO BE LONG WINDED buuuut, I do not know your language background or English level so I'm hoping to be thorough enough for ANYONE to understand if this topic is completely new to them :-D
So Lastly, the other perspective. If you take the texting scenario and make it between persons where ONLY ONE (1) was interested, then Person 2's curve would have been a total shut down.
Besides Urban Dictionary my source is MYSELF, a young lady in America that frequently shuts down fools that don't know the right way to approach women <3 .^_^.
PS- Spurn and Rebuff aren't quite informal. The average group of youth don't get together and talk about how "Tiffany rebuffed David in front of everyone" or how "Amy had to spurn the old guy trying to holler at her at the grocery store."
Cock-block is a #DEAD WRONG term in this situation. Cock-blocking requires a 3rd party. Cock-blocking is stopping two people who want each other from sexual activity.
EX: Every time Monica and Eric are alone in the basement Amy starts watching Disney Movies as an excuse to go down there and dig through boxes.
EX #2: When Damien sleeps over Bianca's her brother pretends to be afraid of the dark so he can stay in her room. That way no one gets frisky.
You can't cock-block yourself and a woman isn't cock-blocking when she rejects weird guys. Cock-blocking is a vulgar term that will raise eyebrows if you say it to an adult or generally decent person.
By the name it does not simply mean "alone time" it's explicit to sex. Keeping that in mind it can be offensive to the female if you tell her "Amy is always cock-blocking don't bring her next time" because she may have wanted to be alone with you without having ANY intentions of having sex with you. Saying cock-block to a girlfriend or potential girlfriend could make her misunderstand your intentions. So save that term for hanging with the guys, lol.
I hope I helped! Next time you head out be prepared to shut down and curve folks that don't come correct! ;-)
P.P.S - The Cold shoulder is also inaccurate because it simply means to ignore by quite literally turning your shoulder or back to the person trying to speak to you. A cold shoulder doesn't always "send someone as far as they can get to" and is usually personal. Some women DO give the cold shoulder to complete strangers, but it is rare, which is why such women are dubbed "Ice Queens"
P.P.P.s - Have no worries, saying that you curved a guy/girl doesn't have any stigmas attached to it. People won't question if you were raised in a bad area or anything like that, they always won't think you are being uppity, it is a perfectly accurate term across social and financial groups.
Oh and to explain why the terms "shutting it down" and "curved" are used
The term shutting it down: When a man is trying to pick you/a female up disrespectfully it is seen that he is "wound up" or "turned up" so we "SHUT IT/HIM DOWN" before he can take things any further. You bring his ego, attitude, erection, etc. down to Earth.
The term curve: It's seen that a person is throwing a flirt/advance like a baseball straight for you but you're decline is the CURVE-ball they didn't see coming. You took them off their beeline course. :)
Best Answer
As is often the case, the dictionary definition is a little "tight" - as you suggest "better half" can, and frequently does, refer to a close partner, regardless of marital status. Usually when used in that way, it refers to a relationship that is almost equivalent to marriage, but even a casual boyfriend/girlfriend relationship is enough for it to make sense.