A reason reason is a reason! How could it not be? Do you have a reason why it shouldn't be? I thought not.
This word means "reason" as in the reason you're studying Japanese, or the reason you're late. That's why it can also mean similar words like motive and excuse.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
I don’t have any specific reason.
Do you have any reason for not having settled your business expenses yet?
For logical reasons, he was led to believe that the culprit in the case of the missing rubber gloves was the balloonist.