丸~ (whole, full)

The prefix 丸 / まる ('round, whole, entire') attached to a number-counter to mean 'a whole, a full, an entire': 丸一日 / まる一日 ('a full day'), 丸三年 ('a full three years'), 丸一週間 ('a whole week'). Emphasizes the completeness of the time period. Equally written in kanji or kana.