I know you can say you were "super glad you did something," but I'm looking for a word that expresses this in nominal form, i.e. the opposite of "my biggest regret." (my biggest ___ ) Does a word like this exist?
I would say the opposite of 'biggest regret' is 'greatest satisfaction'.
Regret is what is felt if one is dissatisfied with an outcome.
Satisfaction is the feeling of achievement, of success.
2a: fulfillment of a need or want b: the quality or state of being satisfied : CONTENTMENT c: a source or means of enjoyment : GRATIFICATION
As noted in comment, the wording 'greatest satisfaction' accommodates to the OP's idiomatic wording 'biggest regret'. 'Big' is a matter of bulk, of burden.
'Great' is a matter of expansiveness, fulness, release.
This is the greatest satisfaction of my life - Shakira, UNICEF Ambassador.
From the definition of regret:
1 a : to mourn the loss or death of
1 b : to miss very much
2 : to be very sorry for
// regrets his mistakes
It was my biggest regret.
In contrast (and with respect to "super glad you did something"), I think of delight:
1 : a high degree of gratification or pleasure : JOY
// children squealing in delight
also : extreme satisfaction
// seems to take delight in the misfortunes of others
2 : something that gives great pleasure
// her performance was a delight
Although it can be used with biggest, it's more natural when paired with greatest:
It was my greatest delight.
From the definition, gratification, joy, satisfaction, and pleasure could also be used—but delight seems to encompass all those senses in a way that the others don't.
In fact, according to Google Ngram Viewer, even regret is more commonly paired with greatest:
Regret expresses the notion that a prior decision or action turned out to be wrong, or would have been done differently if you had the knowledge you had today - it seemed good in the beginning, but turned out to be bad in the end. A word that captures dual aspects of the opposite of this is vindication, which indicates that a previous action or belief turned out to be correct or justified, after a period of doubt - it seemed bad in the beginning (at least to some), but turned out to be good in the end.
His investment in Enron turned out to be regrettable, but his early investment in Google was vindicated.
As pointed out in the comments, vindication requires a some sense of doubt, uncertainty, or opposition in the early stages, so it doesn't capture the general idea of "something you're glad you did", as it doesn't really apply if everyone agrees it was a good idea in the first place.
I feel like the main component of regret is that one thinks about the past often and wishes it could be different. So we want a word/phrase that implies thinks about the past often and is happy with how it went.
So I propose:
fondness - "my fondest memory" or "I look back with great fondness"
Similar to that would be:
tenderness - "I look back with great tenderness"
I think the word you are after is achievement:
noun: achievement; plural noun: achievements
- a thing done successfully, typically by effort, courage, or skill. "to reach this stage is a great achievement"
So you would say something like Completing that project was my biggest achievement at the company.
To regret is to 're-greet', meaning revisit and pore over the decision again and again. The opposite of that suggests completion and moving forward positively, so I'd suggest accomplishment.
If regret conveys the state of mind I wish I had done it,
- one contrary is I do not wish I had done it: relief and synonyms
- another one is I do wish I hadn't done it: remorse and synonyms
- another one is I do not wish I hadn't done it: satisfaction and synonyms
Depends on what one means for "exact contrary".
Not a mother tongue, though. Some of this logic might be unidiomatic, but the relationship between a state of mind in the present and an event in the past gives room to different nuances.
As a single word request, I am unaware of any direct answer to your question where a word could swap regret in " my biggest regret is".
If you think about it, it makes sense that there is no single word antonym for regret, as regret is an emotion, and not all emotions (especially complex ones like regret) have a direct opposite.
If you regret something, that is just how you feel about it, you feel regret.
But to say that something is your biggest [opposite of regret] could mean a few things:
- You're very glad that you did it.
- You are very proud that you did it.
- You feel very satisfied that you did it, etc.
Therefore, English speakers explain in more detail when they are talking about past events, they specify if they're proud of the event, or if it was a defining moment in their life, etc.
I have personally never felt the need for such a single word because in context there is usually more I want to say about the event, like the aforementioned feelings about it.
Assuming that regret is describing the negative reaction or aversion to the consequences of an action taken in the past, then an exact opposite word would be conviction which is a positive reaction of validation to the consequences of an action taken in the past.
Conviction - noun - a strong belief that is not likely to change, or the strong feeling that your beliefs are right:
How about gladness, which is the noun form of glad. From Lexico:
glad: Pleased; delighted.
My biggest gladness OR my greatest gladness.
I prefer the latter.
Gladness captures the nominal form of your "super glad" in a way other words don't. It's also the exact opposite of regret in the context of your question.