A main or central figure in a group or organization, often one that orchestrates activities or plans.

The most important or critical part of something.

किसी चीज़ का सबसे महत्वपूर्ण या विशेष हिस्सा।

English Usage: He is the kingpin in that project, making all the key decisions.

Hindi Usage: वह उस परियोजना में मुख्य व्यक्ति है, सभी महत्वपूर्ण निर्णय लेते हुए।