Undependable

Part of speech: adjective

Definitions

  1. Not reliable or trustworthy; likely to fail when needed or counted upon
  2. Lacking reliability or trustworthiness, an attribute signifying a tendency to fail when called upon or to not meet expectations in various circumstances
  3. Characterized by a consistent inability to provide support or dependability, often resulting in disappointment when relied upon for assistance or commitment

Etymology: The adjective under discussion is formed from the base word "dependable," which itself comes from the verb "depend." The verb "depend" entered English in the late 15th century from the Old French "dependre," which derived from the Latin "dependere," meaning "to hang down" or "to be contingent upon." Originally, the sense was quite literal—something depending on something else was thought of as hanging or suspended from it. Over time, this developed into the more abstract idea of reliance or trustworthiness. Adding the suffix "-able," a common English formation borrowed from French and Latin, turned "depend" into "dependable," meaning capable of being depended upon or reliable. This formation has been in use since at least the 17th century. The prefix "un-" is a straightforward negation added to adjectives to indicate the opposite quality, so "undependable" simply means not dependable or unreliable. There is no particularly dramatic shift in meaning here; the word's components are transparent and the negative prefix clearly signals the opposite of dependable. The word likely entered English usage sometime after "dependable" became common, as speakers needed a term to describe something or someone lacking reliability. Its formation follows a very regular pattern in English morphology, combining a verb base, a capability suffix, and a negative prefix. Thus, the adjective is a product of straightforward English word formation processes rather than a borrowing or a coinage with a specific historical anecdote. It neatly expresses the opposite quality of trustworthiness by negating a well-established adjective that itself traces back to Latin roots emphasizing physical suspension and later abstract contingency.

Synonyms: unreliable, inconsistent, erratic, fickle, untrustworthy

Antonyms: reliable, trustworthy, dependable, consistent, steady