Assertion: stingray's tail | /r/ObjectUse | used for defence
Facets:
Source sentences:
text: The wing-like pectoral fins are used to propel the stingray across the ocean bottom, whilst the slender tail possesses a long, serrated and venomous spine at the base, used for defence.
text: The wing-likepectoral fins are used to propel the stingray across the ocean bottom, whilst the slender tail possesses a long, serrated and poisonous spine at the base, used for defence.