A class of echinoderms also known as sea cucumbers, characterized by their elongated body and leathery skin.

समुद्री खीरा (Samudrik Kheera)

English Usage: "Research on holothuroidea has revealed their important role in ocean ecosystems."

Hindi Usage: "समुद्री खीरा पर शोध ने महासागरीय पारिस्थितिक तंत्र में उनकी महत्वपूर्ण भूमिका का खुलासा किया है।"