Shining brightly with flashes of light; sparkling; can also describe something attractive but possibly superficial or deceptive.
From Old Norse 'glitra' (to glitter), related to 'glisten.' First used in English in the 14th century to describe light reflecting off surfaces; the figurative sense of 'attractive but false' developed later.
'All that glitters is not gold'—this saying exists in multiple languages because humans everywhere noticed that shiny things aren't always valuable, a lesson worth teaching repeatedly!
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