$

An S-shape with one (or, in some typefaces, two) vertical line crossing it completely. See for the usage with explicitly two lines.

$ appears to have evolved ca 1775 in the United States from a common abbreviation for pesos, also known as piastres or pieces of eight, a P/raised-S ligature P^S that passed through a stage resembling ֆ.[1] It was used in the US before the adoption of the dollar in 1785.[2]

(computing): This sense is the result of homophony between English cache and cash, dollars being a form of cash.

$

1. money
   • 1954, Donald's Diary (in English):

     Uncle Ray's Loans
     We lend $$

2. (used everywhere except in the Philippines) peso
3. dollar
   • 1977, advertisement page in Uncanny X-Men, #106, page 8

     Fool all your friends. You'll get a Million^[sic] $$ worth of laughs with these exact reproductions of old U. S. Gold Banknotes (1840).

4. escudo
5. (computing) cache
   • 2010 Fall, U Penn CIS501 lecture notes:

     How to provide additional D$ bandwidth?

• (money):
  • $$ (“(rating) expensive”)
  • English: $$ (“large amount of money”), O$P$ (“owe money, pay money”)
• (cache): English: D$ (“data cache”), I$ (“instruction cache”)

$

1. A substitute for the letter S, used as a symbol of money or (perceived) greed in business practices.

   "Micro$oft Window$"

   • 2015, "Pixtopia", season 1, episode 6b of Star vs. the Forces of Evil

     [the text below is written on-screen in large letters, once Marco reveals his "emergency cash stash"]
     Marco'$ emergency ca$h $ta$h

2. A substitute for the letter S, used as a censored or filter-avoidance spelling.

• (money or greed): English: CO$ (“Church of Scientology”); Micro$oft, M$, M$FT (“Microsoft”); $cientology (“Scientology”)
• (censored or filter-avoidance): English: @$ (“ass”), le$bian (“lesbian”)

$

1. The symbol for the dollar and peso, or by convention, other currency.
2. The unofficial symbol for the escudo.
3. (programming) Prefix indicating a variable in some languages, like Perl, PHP, shell scripts.

When used as a currency symbol, $ precedes the number it qualifies in English, despite being pronounced second. For example, “$1” is read as “one dollar”, not “dollar one” unlike the usage in languages such as French or German: “1 $”, “2,50 $”.

When used for the Portuguese escudo, $ is placed between the escudos & centavos, 2$50. The official symbol for the escudo is (with two bars), but that form is unified with the single-bar form in Unicode. A single-bar dollar sign is frequently employed in its place even for official purposes.

• (currency):
  • A$, AU$ (“Australian dollar”); C$ (“córdoba”); NT$ (“New Taiwan dollar”); NZ$ (“New Zealand dollar”); R$ (“real”)
  • English: C$ (“Canadian dollar; Confederate dollar”); U$, US$ (“United States dollar”)
• (variable): English: $DEITY (“generic deity”)

Currency signs

Formerly used currency signs