the primary or main author of a work

the head or leader of a group or organization

प्रमुख

English Usage: The principal of the school addressed the students.

Hindi Usage: स्कूल के प्रमुख ने छात्रों को संबोधित किया।

most important

सबसे महत्वपूर्ण

English Usage: Her principal concern was the welfare of her children.

Hindi Usage: उनकी सबसे महत्वपूर्ण चिंता अपने बच्चों की भलाई थी।