The compound "tell-tale" is a native English formation, combining two words of Germanic origin with closely related meanings. The verb "tell," originally meaning "to count" or "to recount," joined with the noun "tale," meaning "a story" or "an account." The compound's literal sense, "one who tells tales," emerged in the 16th century, specifically referring to someone who reveals private or incriminating information about others, often a tattletale. Over time, the meaning broadened from a person to any object or sign that inadvertently reveals or betrays information, leading to its modern adjectival use describing something that serves as a revealing indicator.

Structure: tell (to relate) + tale (a story) - tell: From Old English tellan (to count, relate, recount), of Germanic origin. Functional role: Verb root meaning to narrate or make known. - tale: From Old English talu (story, account, number), of Germanic origin. Functional role: Noun root meaning a narrative or account.