To dream of using a dictionary represents caring about what other people's opinions are. Asking yourself what you're doing or thinking would mean to someone else.
Negatively, a dictionary may be a sign that you are allowing others opinions too much power over the management of your affairs.
Example: A woman dreamed of picking up a dictionary. In waking life her father was in a coma and doctors told her he had no chance to recover. She asked the doctor to give her his definition of death.