As a proper noun illinois
is a capital: springfield largest city: chicago.
As an adjective illinois
is of or relating to the (
miami-illinois language).
As a noun illinois
is any of a tribe of native americans who formerly occupied the region between the wabash and mississippi rivers.
As a letter d is
the fourth letter of the.
As a numeral d is
cardinal number five hundred (500).
As a symbol d is
deuterium, when it needs to be distinguished from ordinary hydrogen.