To dream of a whale represents issues in your life that are so powerful or influential that everything else is insignificant. Enormous accomplishments that can't be outdone.
Positively, a whale reflects a positive situation that is so powerful that all your worries or frustrations become null. Some area of your life where you are too big to lose.
Negatively, a whale reflects a situation that is so powerful that all your desires or goals are diminished. Feeling that something in your life is too big for you to deal with. Feeling too little to compete or handle yourself on your own. Feelings about yourself being so accomplished that nobody could ever do anything bigger than you.
Example: A young girl dreamed of being chased by a whale. In waking life she was about to enter high school and feared not having enough friends and not being popular enough. She felt like a "little fish" that didn't know anyone.
Example 2: A woman dreamed of seeing a smiling whale. In waking life she had just finished climbing an enormous mountain with her husband. The whale may have reflected her feelings about her mountain climb be so such an enormous accomplishment that nobody else she knew could ever achieve more.
Example 3: A woman dreamed of being on vacation and fearing that a whale would attack her. In waking life she was trying to calm herself down from a very stressful issue, but the issue was too important for her to stop worrying about.
*Please See Killer Whales