Once, twice, thrice, what is next?

Today’s English
September 23rd, 2017

If something is done one time, we use “once" and subsequently twice and thrice but what is the word for something done four times? Next to third, there is fourth but next to thrice, there is no term in English like this for 4 times.  Once not only means one time but also sometimes in the past,  rarely /occasionally/ now and then (once in a blue moon, once in a while),  finally (once and for all).suddenly (all at once), immediately (at once), and long time ago (once upon a time). 

1.Once I attended a meeting here with my friend. (Sometimes in the past)
2.Please inform me the progress once in a while (= now and then)
3.I warn you once and for all. Don't repeat this again. (As the first and last one)
4.The door opened all at once and the income tax officers came in. (=suddenly)
5.Do it at once. (=immediately)

If you want to justify your expenditures for a celebration, use the expression -Christmas /Diwali comes but once a year.  Your job soon enters your blood and becomes your character. Whatever you speak or do, unconsciously you will be throwing its shadows. This is what we say by using the English expression – “once a priest, always a priest.” ( here you can put any profession after once, not only priest).
1.Why do you waste this much money for this function? You know, Diwali comes but once a year.
2.Even at home, he was lecturing to all. Once a lecturer, always a lecturer.
3.He accounts for each expense accurately.  Once an accountant, always an accountant.

You can also use “opportunity knocks at your door but once” to encourage someone to try and “once the dust has settled..” to deal with something when it calms down.”
1.Why do you think a lot? Opportunity knocks at your door but once.
2. Once the dust has settled, you can find solution for this problem. Walt for a while.

“Cowards die many times before their deaths;
The valiant never taste of death but once. “
Shakespeare, “Julius Caesar”