刺丝胞

cnidocyte / nettle cell of medusa or anemone

(onom.) whoosh

thorn / sting / thrust / to prick / to pierce / to stab / to assassinate / to murder

silk / thread / trace / (cuisine) shreds or julienne strips / CL:條|条[tiao2] / classifier: a thread (of cloud, smoke etc), a bit, an iota, a hint (of sth) etc

placenta / womb / born of the same parents

Cnidaria (animal phylum including jellyfish and sessile polyps)