I. myr ‧ i ‧ ad 1 /ˈmɪriəd/ BrE AmE adjective [usually before noun] written
very many:
the myriad causes of homelessness
a myriad
We were plagued by a myriad tiny flies.
II. myriad 2 BrE AmE noun
[ Date: 1500-1600 ; Language: Greek ; Origin: myrioi 'too many to count' ]
a myriad of something/myriads of something a very large number of things:
We’re still studying a myriad of options.