An agent that works together with or in conjunction with another.

A substance that assists in a specific process.

एक पदार्थ जो एक विशेष प्रक्रिया में सहायता करता है।

English Usage: The coactant played a crucial role in the synthesis of the new compound.

Hindi Usage: सहक्रियता ने नए यौगिक के संश्लेषण में महत्वपूर्ण भूमिका निभाई।