This is the 16768th most frequent Russian word.
сложить
To add, fold, or put together.
The word 'сложить' is used in the meaning of 'to stack' or 'to arrange' items neatly.
Я сложил бумаги на столе.
I stacked the papers on the table.
The word 'сложить' is used in the mathematical sense of 'to add' numbers.
Она умеет сложить два числа быстро.
She can add two numbers quickly.
Here, 'сложить' implies 'to combine' or 'to unite' efforts.