Tiara (disambiguation)
Diadem stands for:
- Diadem , a headband
- Diadem (book series) , a book series by the British writer John Peel
- the proper name of α Comae Berenices , a star
- Diadem (rose) , a variety of rose
- a computer program from National Instruments , see NI DIAdem
- since 1960 a product name of the Fulda Reifen company (today Goodyear)
- Diadem (band name), a music project with Diether Dehm (album " Grosse Liebe.Reloaded ")