The letter mentioned my great aunt and uncle only incidentally.

信里只是附带地提到我的叔祖母和叔祖父。

《柯林斯英汉双解大词典》

The information was only discovered incidentally.

这个信息只是偶然得到的。

《牛津词典》

Incidentally, have you heard the news about Sue?

顺便问一句，你听说过休的事了吗？

《牛津词典》

It's voluntary incidentally, it's not mandated.

VOA: special.2010.02.05

One peculiar property of this--incidentally, at every point of time this thing holds, this is time to maturity.

顺便说一下这个公式一个特别的性质,这个等式在任何时候都成立,这是贷款剩余期限

耶鲁公开课 - 金融市场课程节选

She also loves astronomy, which is incidentally an interest of mine too, but you won't hear about it again in this course.

她还喜欢天文学,巧合的是,这也是我的爱好之一,但在这节课上我也不会提及

耶鲁公开课 - 金融市场课程节选

Not incidentally, Mr. Marden created this painting at his studio in Eagles Mere, Pa.

WSJ: A Flower Arrangement Inspired by Art

That matches the lowest estimate around for iPhone 5 sales in the same time period, incidentally.

FORBES: iPhone 'Math': The Bigger Screen Adds Up

Beyond that, however, Tizen at least seems capable of delivering smartphone fundamentals like a fast camera (with burst mode, incidentally).

ENGADGET