Preconceive is a word that means to form an idea or opinion about something before encountering or investigating it. There are several synonyms for preconceive that can add variety and nuance to your language. Some alternatives include prejudge, assume, presume, conjecture, and speculate. These words all imply forming an opinion before having all the necessary information. However, there are subtle differences between them. Prejudge and assume both suggest forming an opinion without evidence, while presume implies a more reasonable assumption. Conjecture and speculate suggest forming an opinion based on limited evidence or guessing. Consider these synonyms when you want to add precision and variety to your writing or speaking.