What does 拡散 mean?
拡散 is a Japanese noun meaning “scattering, diffusion” in English. It can also be translated as “diffusion (of light, gas)” depending on context. It is written as 拡散 in kanji, かくさん in hiragana, and kakusan in romaji. This word is part of JLPT N1 vocabulary.
Example sentence
科学者たちはエイズ・ウイルスの拡散をくい止めようと戦っています。
Scientists are fighting to stem the spread of the AIDS virus.