Passai (拔塞) also known as "Bassai" is the name of a group of kata practiced in different styles of martial arts, including karate. There are 2 version of these kata," Bassai-dai" (大 / major) and "Bassai-sho" (小 / minor).
In his 1922 book, Gichin Funakoshi names the form "Passai" and provides no Kanji characters to go along with this name. The Okinawans did not have a clear definition for the name "Passai" for Funakoshi to translate into Japanese, so he substituted it with a similar sounding kanji, "Bassai".
In Chinese "拔" (bá) can mean "to seize or capture"; and "塞" (sāi) means a "place of strategic importance/fort". Thus Funakoshi's characters of "Bá sāi" (拔塞) would mean "to seize or capture a place of importance/fortress." However the 1973 translation of "Karate-do Kyohan" lists Funakoshi's explanation of the form name as "Breaking through an enemy's fortress."
Further evidence that "Bassai" has roots in Tomari (city in Okinawa) is that "Bassai-dai" starts with the right fist covered by the left hand, like other kata thought to have originated there, such as Jitte, Jion, Jiin and Enpi.
The kata focus is the idea of changing “disadvantage” into “advantage” by strong and courageous response, switching blocks and differing degrees of power. (Bassai-dai starts with 9 back to back blocks).
There is 2 version of “Bassai” kata - "Bassai-Dai" and "Bassai-Sho"
The suffix -dai (大) means "large,major" and -sho (小) "small,minor"
Bassai can be literally translated "to seize or capture a place of importance/fortress"
The Bassai kata are usually classed as intermediate kata
Root: "Tomari-te" school of kata in Okinawa