This is a Japanese word meaning Explosion/Loud. It is also the nickname for the Character Katsuki Bakugou from an anime: Boku No Hero Academia (My Hero Academia). Bakugou's quirk is to let him make explosions from the sweat on his hands. His father's quirk is explosion - which is made from his sweat - is very weak as it has no fuel to power it. Bakugou's mother's quirk is glycerin which will be the fuel to Bakugou's quirk: Explosion. Bakugou is a very explosive person and is usually called this nickname by Deku (Izuku Midoriya)
"Kacchan!" Deku exclaimed, "Are you OK?"
Bakugo responds: "I DON'T NEED YOUR HELP DEKU!!!!!!!!"
“Kacchan!” Izuku Midoriya voiced breathlessly as he pleaded for mercy from the explosive boys grasp. Blood streaming down his face; he had tried to convince the boy that a fight wasn’t necesssry but that ultimately failed.