Translation guide
The scientific theory that matter is composed of discrete units called atoms. In Japanese, this is typically expressed with the term 原子論 (genshiron) or 原子説 (genshisetsu).
The scientific concept that all matter is made of atoms.
The most common and standard term for atomic theory in scientific contexts.
原子論は古代ギリシャに起源を持つ。
Atomic theory has its origins in ancient Greece.
An alternative term, often used interchangeably with 原子論, but can sometimes imply a hypothesis or doctrine rather than a fully established theory.
ドルトンの原子説は近代化学の基礎となった。
Dalton's atomic theory became the foundation of modern chemistry.