look up any word, like half chub:
 
1.
1. The mate from a past relationship or friendship who, in the present reality, seems the ideal match, if it weren't for some force beyond your control, fate or otherwise, keeping you apart.
2. In virtually any context, someone you meet and share a significant encounter with who holds qualities akin to "the one" but for circumstance sake you are separated from; always after the fact.

3. The person dated casually, but never seriously, who could have been more.
4. In Bro Parlance: The one girl who a guy liked but with whom he never quite connected or "scored".
5. More broadly, any love regret More apt: A One That Got Away.

Origin: Fishing phrase.
1. She hadn't seen James in years. And when she did, she wondered why they had ever broken up. All of a sudden she thought he might be The One That Got Away.
2. They had met on vacation, and he knew it was going be short. But Tom still considered Kayla to be The One That Got Away.
3. He had dated Rose during freshman year of college, but they decided to be friends and they've been close ever since. Every now and then he remembers what it was like to kiss her. Maybe she was The One That Got Away.
4. The girl you go to your 10 year high school reunion for: Maybe I can have that chance I never got with The One That Got Away.
5. Sally always wondered why Jeff had never called; she did have a a great rack, after all. He was just The One That Got Away.
by yozinator March 17, 2011
 
2.
The person that you could've and should've ended up with but didn't, usually because of a series of poor choices on your end. You pine over them and wonder what could've been all the while stalking them through mutual friends and on facebook, becoming extremely jealous over anyone that looks twice at them. You try to express your regret but they usually won't believe you unless you do some sort of grand gesture. The one that got away is someone that you will forever regret. In other words Trevor Sharod White.
I should've treated Roddy better, he is definitely the one that got away!
by 1scooby August 14, 2011