blah vs bright

Dull; uninteresting; insipid. 

Low in spirit or health; down. 

(in plural, the blahs) A general or ambiguous feeling of discomfort, dissatisfaction, uneasiness, boredom, mild depression, etc. 

Nonsense; drivel; idle, meaningless talk. 

An expression of mild frustration. 

Representing the sound of vomiting. 

Imitative of idle, meaningless talk; used sometimes in a slightly derogatory manner to mock or downplay another's words, or to show disinterest in a diatribe, rant, instructions, unsolicited advice, parenting, etc. Also used when recalling and retelling another's words, as a substitute for the portions of the speech deemed irrelevant. 

Of a scent or taste: not bland or mild; bold, sharp, strong. 

Of a musical instrument, sound, or a voice: clearly audible; clear, resounding, and often high-pitched. 

Of the face or eyes, or a smile: showing happiness or hopefulness; cheerful, lively. 

Of an object, surface, etc.: reflecting much light; having a high lustre; gleaming, shiny. 

Of an object, surface, etc.: having vivid colour(s); colourful. 

Of a colour: not muted or pale; bold, brilliant, vivid. 

Clearly apparent; conspicuous. 

In good spirits; happy, optimistic. 

Of climate or weather: not cloudy or gloomy; fair; also, of a period of time, the sky, etc.: characterized by much sunshine and good weather. 

Of conversation, writing, etc.: imaginative or sparkling with wit; clever, witty. 

Of an opportunity or outlook: having a reasonable chance of success; favourable, good. 

Of a place: not dark; well-lit. 

Of a period of history or time: happy, prosperous, successful. 

Of light: brilliant, intense. 

Of a person: lively, vivacious. 

Glorious; illustrious. 

Emitting much light; visually dazzling; luminous, lucent, radiant. 

Having a clear, quick intellect; intelligent. 

Of a rhythm or tempo: lively, upbeat. 

Of a metal object or surface: lacking any protective coating or surface treatment for the prevention of corrosion. 

Of a substance: clear, transparent; also, pure, unadulterated; (specifically) of wine: free of suspended particles; not cloudy; fine. 

Of a room or other place: having acoustic qualities that tend to cause much echoing or reverberation of sound, particularly at high frequencies. 

A person with a naturalistic worldview with no mystical or supernatural elements. 

Something (especially a product intended for sale) that has vivid colours or a lustrous appearance. 

An artist's brush used in acrylic and oil painting with a long ferrule and a flat, somewhat tapering bristle head. 

Often followed by up: to become bright (in various senses); to brighten. 

Often followed by up: to cast light on (someone or something); to brighten, to illuminate. 

Often followed by up: to cause (someone or something) to be bright (in various senses); to brighten; specifically, to make (someone or something) energetic, or happy and optimistic.