Pinoy is a demonym used by Filipinos for their compatriots in the Philippines and around the world. Filipinos usually refer to themselves informally as Pinoy or some times feminine: Pinay,
which is formed by taking the last four letters of the word 'Filipino' and adding the diminutive suffix -y. The word was coined by expatriate Filipino Americans during the 1920s and was later adopted by Filipinos in the Philippines.
Pinoy is a term of endearment and is rarely used in formal settings. The term is akin to that of a nickname which is used by close family members and friends so that one who uses it somehow already developed some close ties with Filipinos.
The term especially gained popular currency in the late 1970s in the Philippines when a surge in patriotism made a hit song of Filipino folksinger Heber Bartolome's "Tayo'y mga Pinoy" (We are Filipinos), and later with famous Filipino band Bamboo's "Noy-pi" (Pinoy in reversed syllables).
In addition to Pinoy, Filipinos also refer themselves as Filipinos and Filipinas, Filipinos for the male gender (masculine), and Filipinas for the female gender (feminine).
Nowadays, it is used as an adjective to some terms highlighting their relationship to the Philippines or Filipinos.