IPA: //ʌnˈsteɪnd//
KK: /ʌnˈsteɪnd/
Not marked or affected by any stains; clean and pure.
The tablecloth was unstained, making it perfect for the dinner party.
Unstained → It is formed from "un-" (meaning not) and "stained" (from Old English "stǣnan", meaning to mark or color). The word "unstained" means not marked or colored, indicating purity or cleanliness.
Think of 'not' ('un-') being added to 'marked' ('stained') — that's why unstained means something that is not marked or remains pure.