A History of Short Words

From the New York Times Crossword Puzzle

RHO

Thu, 4 Jan '24
Plato's "P"
Sun, 10 Dec '23
P, to Plato
Sun, 24 Sep '23
?
Thu, 1 Jun '23
Fraternity row letter with a homophone in this clue
Tue, 7 Mar '23
Greek "P"
Tue, 19 Jul '22
Letter after pi
Tue, 14 Jun '22
Letter after pi
Mon, 23 May '22
P, to Plato
Sun, 1 May '22
P
Sun, 27 Mar '22
Pi follower
Wed, 2 Mar '22
Pi follower
Sun, 30 Jan '22
Plato's P
Wed, 12 Jan '22
Greek "P"
Sun, 14 Nov '21
Sorority letter
Sun, 19 Sep '21
Letter two before tau
Wed, 1 Sep '21
Letter after pi
Tue, 1 Jun '21
Letter after pi
Sun, 30 May '21
Fraternity letter
Sat, 8 May '21
Sorority letter
Tue, 13 Apr '21
Greek letter that looks like a "P"
Fri, 2 Apr '21
Letter seen in a Christogram