noun🔗ShareNematocystenA capsule, in certain cnidarians, containing a barbed, threadlike tube that delivers a paralyzing sting"When the jellyfish brushed against the swimmer's leg, the nematocysts fired, injecting venom and causing a painful sting. "Als die Qualle das Bein des Schwimmers berührte, feuerten die Nematocysten ab, injizierten Gift und verursachten einen schmerzhaften Stich.biologyanimalanatomyorganismChat with AIVocabulary GamePractice Reading