unspeakable adjective 5noun 1forms 3 adjective5 •Incapable of being spoken or uttered.The endless pride and outstretching of man, unspeakable joys and sorrows. — 1855 •Extremely bad or objectionable. •Impossible to speak about. •Unfit or not permitted to be spoken or described. •That cannot be referenced in source code, due to having no usable name.unspeakable field names — 2008 noun1 •Something that cannot or must not be spoken about.The longer we don't speak about the unspeakables, the more harm they do to the relationship. — 2009 formsunspeakables · more unspeakable · most unspeakable