There are lots of Japanese loan words in English. The usual examples include sushi, samurai and maybe futon and tofu. It appears that you can add gyoza to the list:
Being on a list of Scrabble (a popular word game where you place letter tiles on the board to create words) possibilities may not mean that the word is understood by the general English-speaking public, but it does add to the list of food-related Japanese loan words already in circulation (azuki, edamame, kombucha, mikan, nashi, natto, wasabi, and many, many more).
Wikipedia has one list of English words of Japanese origin. The food category is longer than the rest. But there are quite a few words on this list that I don’t suppose most English-speakers use or even know, unless they are especially interested in that particular culture (bunraku, kakemono, urushioi, for example).
This post from Language Log asks “Too many Japanese loanwords in English?” and suggests that there are far more loanwords from Japanese than, say, Chinese.
This list includes brand names (Uniqlo, Mazda, Toshiba…) but may have a few words that you might be surprised to be used by many English speakers.
The post also talks about how English has permeated the Japanese language, especially in the business world. For example:
Whereas I just think of “Pulp Fiction”… (beware: some bad words in this clip)
Back to the ubiquity of English words in Japanese business, there’s also this from the Language Log post: