Does English have a word for "not sick"?

single-word-requests word-usage translation

"feeling well" is generally (as in almost always) used with health so yes, "Not sick" is synonymous with "well".

You can also use "in good health".

As pointed out above "feeling unwell" means "sick".

Although it should be noted that "sick" is ambiguous (nauseous, in bad health, unwell etc)

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