for a second time; again
Used adverbially with verbs to indicate doing something a second time. Often appears in set phrases like 二目と見られない (too horrible to look at again).
その光景は二目と見られないほど悲惨だった。
The scene was so tragic that I couldn't bear to look at it a second time.
二
I missed a once-in-a-lifetime opportunity.
Compound of 二 (two, second) and 目 (ordinal suffix). The reading ふため follows the native Japanese (kun'yomi) pattern.