The term 'conceive of' can be defined as to form an idea or plan in one's mind. It can be broken down into three crossword solutions: ENVISAGE (8 letters), IMAGINE (7 letters), and IDEATE (6 letters). ENVISAGE means to form a mental image of something, while IMAGINE implies creating a mental picture of something that is not real. Finally, IDEATE means to form an idea or concept. All three words are related to the concept of forming an idea or plan in one's mind.