Taʿarraḍat is a third-person feminine singular perfect, with al-thurayyā as its subject. Taʿarruḍa is a verbal noun from the same base, used as a cognate accusative to characterize the action.
Athnāʾi al-wishāḥ evokes the separate parts or sections of an ornament. Al-mufaṣṣal qualifies a sash set with discrete decorative pieces. The spaced yet ordered appearance of stars is thus rendered through a crafted human object.
ExpressionGrammatical or rhetorical role
TaʿarraḍatVerb describing the star cluster
TaʿarruḍaCognate accusative (mafʿūl muṭlaq)
Athnāʾ al-wishāḥParts of the compared ornament
Al-mufaṣṣalQualification of the jeweled sash