A History of Short Words

From the New York Times Crossword Puzzle

CCS

Mon, 20 May '24
Includes on an email, for short
Tue, 5 Mar '24
Syringe amts.
Mon, 4 Mar '24
Loops in, on an email
Fri, 16 Jun '23
Includes, in a way
Wed, 17 May '23
Includes on a thread
Tue, 6 Dec '22
Vaccine units, in brief
Sat, 16 Jul '22
E.R. units
Sat, 16 Apr '22
Syringe amts.
Mon, 4 Apr '22
Loops into an online convo
Tue, 25 Jan '22
IV amounts
Sun, 5 Dec '21
They're found below the "To" field
Mon, 31 May '21
Adds to an email chain, in a way
Tue, 30 Mar '21
Loops in, in a way
Sun, 7 Feb '21
Keeps in the loop, in a way