This is the 5726th most frequent Japanese word.
つかっ
"つかっ" is not a complete word; it appears to be part of the verb "使う" (つかう), meaning "to use."
Refers to utilizing an object for a purpose, in this case, a pen.
このペンをつかったことがありますか？
Have you ever used this pen?
Indicates permission to use a particular item, a washing machine.
その洗濯機をつかってもいいですか？
May I use that washing machine?
Describes the purpose of employing an object, specifically for looking up unknown words.