This is the 181st most frequent Ukrainian word.
сил
The Ukrainian word "сил" is the genitive plural form of "сила," meaning "strength" or "force."
The word 'сил' (forces/strength) is used here in the plural form to denote personal energy or effort exerted towards accomplishing a task.
Я доклав усіх сил, щоб завершити цей проект.
I put in all my strength to complete this project.
'Сил' refers to the resource of personal strength or capacity required for an activity, expressed in a context of deficiency.
Йому не вистачає сил, щоб продовжити цю роботу.
He lacks the strength to continue this work.
In this context, 'сил' is used to describe the phenomena or powers of nature, indicating its greater and external concept.