给定一个英语单词，请提供其定义、同义词和反义词。
Happiness
Definition: A mental or emotional state of well-being characterized by positive emotions ranging from contentment to intense joy. 

Synonyms: Joy, Delight, Bliss, Pleasure, Cheerfulness. 

Antonyms: Sadness, Misery, Sorrow, Grief, Despair.