Which reference material gives definitions of words?

Which reference material lists synonyms and antonyms?

What would be the best resource to use if a question asked for the pronunciation of a word?

What would be the best resource to use if you needed a synonym (similar word) for "quiet?"

You want to revise your story and replace words you have repeated over and over. What source do you use?

"Rex is so sleepy today, he may not be reliable."

What is a synonym (similar word) for the word reliable?

Rita felt tired because of her restless night of sleep.

What is an antonym (opposite word) for the word restless?

"Students are required to complete all five assignments."

What is an antonym (opposite word) for the word required?

"I need to remember these facts for my quiz!"

What is a synonym (similar word) for the word remember?

Which definition for the word, humor, applies to to this sentence?

"The play we saw was full of dark humor."

Which definition for the word, humor, applies to to this sentence?

"Mary humored her brother, even though she disagreed with him."

Which definition for the word, humor, applies to to this sentence?

"Jim is in a poor humor today."

Which definition for the word, humor, applies to to this sentence?

"Did you find the story humorous at all?"

Which definition for the word, humor, applies to to this sentence?

"I don't understand Mandy's sense of humor."

"I dress in a more relaxed way when I work from home!"

What is an synonym (similar word) for the word relaxed?