a partner or mate that is not currently matched with another

बिना साथी

English Usage: The unmated birds were calling out in hopes of attracting a mate.

Hindi Usage: बिना साथी चिड़िया जोड़े को आकर्षित करने की उम्मीद में चीख रही थी।

to not have a counterpart or mate; to remain single

साथी न होना

English Usage: He remained unmated during the breeding season.

Hindi Usage: वह प्रजनन काल में साथी के बिना रहा।