English
lightbrained
light + brained
Proto-Indo-European *lewk- ‘to shine’
…
Proto-Germanic *leuhtą
Proto-West Germanic *leuht ‘light’
Old English lēoht
Middle English light ‘light, illumination’
English light
Today it means
adj Synonym of light-headed (“thoughtless, frivolous”).
Language periods are conventional ranges, not dates for this word.
Etymograph / lightbrained