Vocabulary: resilience vs resiliency

Tutoring English, you encounter curiosities. The tutor mentions one.

English is great because of its surprising details (that, no doubt, can make it a challenging language).

Resilience means the same as resiliency. I had to look them up to make sure.

Source:

Mish, Frederick C. (editor). The Merriam-Webster Dictionary. Springfield: Merriam-Webster, 2004.