What is an adjective?

The simplest definition of an adjective is that it is a word that describes or clarifies a noun. Adjectives describe nouns by giving some information about an object’s size, shape, age, color, origin or material.

• It’s a big table. (size)
• It’s a round table. (shape)
• It’s an old table. (age)
• It’s a brown table. (color)
• It’s an English table. (origin)
• It’s a wooden table. (material)
• It’s a lovely table. (opinion)
• It’s a broken table. (observation)
• It’s a coffee table. (purpose)

taken from: http://grammar.yourdictionary.com