The compound noun "well-wisher" is a transparent construction from native English elements. Its first element, "well," functions adverbially, modifying the verb "wish" to specify the nature of the desire as being for good fortune. The agent suffix "-er" then nominalizes the phrase, creating a label for a person characterized by this benevolent sentiment. The term emerged in the early 17th century, logically combining these common words to fill a lexical gap for describing a person who expresses goodwill towards another, reflecting a straightforward and enduring social concept.

Structure: well (in a good way) + wish (to desire) + er (person who does) - well: From Old English wel, meaning "in a good way, satisfactorily." An adverb used here in a compound sense. - wish: From Old English wȳscan, meaning "to wish, desire." A verb root. - er: From Old English -ere, an agent noun suffix meaning "one who does or performs an action."