The term Macronutrients (macros) stems from the Greek word "makros", meaning large. Macronutrients are nutrients you require in large amounts. They are needed in such large quantities because they supply all of your daily energy.

Macronutrients are essentially your calories from food broken up into three major nutrient groups:

Carbohydrates
Protein
Fat
Each macronutrient provides important nutrients for daily function and survival, and getting the right balance of all three is crucial for maintaining lean muscle, burning fat and staying healthy. Meaning they may play a key role in determining your body composition. They also play a part in supporting better energy control, mood balance, appetite, and overall fitness performance.
https://www.trifectanutrition.com/blog/how-to-count-macros-a...