The story
From dex- + -a- + -methasone (“prednisone or prednisolone derivative”).
Etymology from Wiktionary, CC BY-SA 4.0.
dexamethasone
Today it means: A synthetic member of the glucocorticoid-class of steroid hormones, having the chemical formula C₂₂H₂₉FO₅, and used especially as an anti-inflammatory agent. Full definition →