This is the 11935th most frequent Spanish word.
imperfecta
Imperfecta: imperfect; not complete or flawless.
Here, 'imperfecta' is used as an adjective to describe a noun (sheet of paper) lacking perfection or having a flaw.
La hoja de papel era imperfecta debido a un corte desigual.
The sheet of paper was imperfect due to an uneven cut.
In this case, 'imperfecta' serves as an adjective indicating an incomplete or flawed state of understanding.
Su conocimiento del tema es imperfecta porque no ha estudiado lo suficiente.
Her knowledge of the subject is imperfect because she hasn't studied enough.
The word 'imperfecta' is used as an adjective here to convey the aesthetic notion of beauty in flaws.