Executive order
Also called EO, presidential order
An order the US president gives the federal executive branch; each is numbered and published in the Federal Register.
How do executive orders relate to the stock market?
Executive orders set how the executive branch acts without new legislation. Many bear directly on specific industries: tariffs, energy, semiconductors, pharmaceuticals.
Tariffs are also announced by proclamation. The effective date and details often follow later, so the dates matter.
Whalegun's Trump page summarises executive orders and tariff announcements in Korean, with the related sectors and how their stocks moved afterwards.