The word swasthya in Sanskrit refers to health.
I came across a very interesting interpretation by Sage Ashtavakra of Ashtavakra Gita fame. He was ashta-vakra because of his 8 physical deformities.
Could such a person be perfectly healthy or swasthya?
Seems impossible, but he was!
How?
Because his physicality was irrelevant to him. All he cared about, was being forever established in the Self.
Which is swa-stitha, or self-established. How cool is that?