How to Say "non-regular" in Spanish
The Spanish word for “non-regular” is “extraordinario” — B2 level.

Examples
Tuvimos una reunión extraordinaria para discutir la crisis financiera.
We had a special (unscheduled) meeting to discuss the financial crisis.
Los gastos extraordinarios de este mes superaron el presupuesto.
The non-regular expenses this month exceeded the budget.
Se convocó a una sesión extraordinaria del congreso para votar la ley.
An extraordinary (special) session of congress was called to vote on the law.
Meaning Confusion
Mistake: “Using 'extraordinario' to mean 'amazing' when describing a formal meeting (e.g., 'La reunión fue extraordinaria' meaning 'The meeting was amazing').”
Correction: In formal contexts, 'reunión extraordinaria' usually means 'special/unscheduled meeting.' If you want to say the meeting was amazing, use 'excelente' or 'fantástica'.
Related Translations
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