testingly

adverb2

1. •
   In a tentative and experimental manner.

   • I have lived as a spoiled child and you have lived as an exposed child, and now those children are looking testingly at each other. — 1994
2. •
   In a challenging manner; so as to test the stamina, patience, etc.

   • ...whether the exercises took place in recognized military training areas or in territory testingly unfamiliar to the troops. — 2005