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Webster 1828 Edition

adv.

Mischievously; destructively.

This practice hath most shrewdly passed upon thee. Obs. Shak.

2. Vexatiously; used of slight mischief.

The obstinate and schismatical are like to think themselves shrewdly hurt by being cut from that body they chos not to be of. Obs. South.

Yet seem'd she not to winch, though shrewdly pained. Obs. Dryden.

3. Archly; sagaciously; with good guess; as, I shrewdly suspect; he shrewdly observed.

shrewdly ‎(comparative more shrewdly, superlative most shrewdly)

In a shrewd manner.
- 1915, Mrs. Belloc Lowndes, The Lodger, chapter I:
  Thanks to that penny he had just spent so recklessly [on a newspaper] he would pass a happy hour, taken, for once, out of his anxious, despondent, miserable self. It irritated him shrewdly to know that these moments of respite from carking care would not be shared with his poor wife, with careworn, troubled Ellen.