Without grief or sorrow; free from sadness or mourning.
From 'grief' plus '-less' (a suffix meaning 'without'), creating an opposite antonym to griefful.
The '-less' suffix is incredibly productive in English—you can attach it to almost any noun to negate it, which is why we have both 'griefful' and 'griefless' as opposites, even though only one of them is commonly used today.
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