Simple Definition of diadem

from our Learner's Dictionary

diadem

noun

ˈdajəˌdɛm

plural diadems

literary : a crown that is worn especially by a king or queen as a symbol of royalty

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“Diadem.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/diadem. Accessed 21 Jun. 2026.

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