The word "resilience" originates from the Latin word "resilire," meaning "to jump back" or "to recoil."   The Latin verb "resilire" is derived from "salire," meaning "to leap".  This Latin root is also the basis for words like "sally" and "somersault". In essence, the core meaning of resilience, both etymologically and in its modern usage, is the ability to bounce back from adversity or a challenging situation.  

Today, resilience is used in a wide range of fields, including psychology, sociology, engineering, and ecology, to describe the capacity to withstand and recover from challenges.  

According to the Oxford English Dictionary, the first use of the word "resilience" in the English language was in 1626, in Francis Bacon's Sylva Sylvarum.  The OED defines this early usage as "an act of rebounding or springing back; rebound recoil."  While the initial usage was related to physical rebounding, the meaning of resilience has evolved. The OED indicates that a second definition, associated with elasticity, was added in 1824. 

The Oxford English Dictionary indicates that the word "resilient" was first used in English in the mid-1600sm specifically in 1644.  The OED's earliest example is from the writings of John Bulwer,  a medical practitioner and writer.

Examples of "resilience" and "resilient" used in a sentence: 
"But as the day went on they started to find some resilience."
"Almost 200 Californians turned out for tips on how to build resilience."
"Family therapists may be their best allies in passing on resilience." 
"Cold temperatures cause the material to lose resilience." 
"The rescue workers showed remarkable resilience in dealing with the difficult conditions."
"That speaks to what has been a theme of this year – the resilience of this team." 
"Even my doctors were surprised at how resilient I was during and after treatment."
"We realized how resilient these women and children had to be."
"In the study, resilient people were easily comforted by positive memories of their deceased partner."