English
lunar caustic
From lunar (“[alchemical] silver”) + caustic.
Formed from lunar ‘alchemical silver’ + caustic
Proto-Indo-European *lewk- ‘bright’
…
Proto-Italic *louksnā ‘moon’
Latin lūna ‘moon’
Latin lūnāris ‘of or pertaining to the moon, lunar’
Middle English lunar ‘shaped like the crescent moon’
English lunar
Proto-Hellenic *káwyō
Ancient Greek καίω ‘I burn’
Ancient Greek καυστός ‘burnt’
Ancient Greek καυστικός ‘burning’
Latin causticus ‘burning’
English caustic
Today it means
noun Silver nitrate fused into a stick and used for cauterizing and as a disinfectant before modern antibiotics.
Language periods are conventional ranges, not dates for this word.
Etymograph / lunar caustic