As in Gartley chart patterns define by Harold McKinley Gartley in the mid 1930's. Also know as Harmonic chart patterns.
The Gartley “222” pattern is named for the page number it is found on in H.M. Gartleys book, Profits in the Stock Market. Gartleys are patterns that include the basic ABCD pattern but are preceded by a significant high or low.
As time went by, the popularity of the Gartley pattern grew and people eventually came up with their own variations.
For some odd reason, the discoverers of these variations decided to name them after animals; common ones being the
Butterfly, Crab and Bat.
Source (incl diagrams):
https://www.babypips.com/school/summer-school/harmonic-price-patterns/the-gartley-and-the-animals.html
See also:
https://www.investopedia.com/articles/forex/11/harmonic-patterns-in-the-currency-markets.asp
https://www.tradingview.com/chart/butterflypattern/
