The term "lighted upon" basically means to stumble upon or chance upon something. However, its antonyms can be words like overlook, disregard, ignore, neglect, and miss. These words signify the opposite of "lighting upon" since they imply a failure to discover or recognize something. The term "overlook" means to miss or fail to notice something. Similarly, "disregard" signifies to disregard or ignore something. "Ignore" means to pay no attention to something or someone. "Neglect" implies failure to take proper care of something. Lastly, "miss" means to fail to see or notice something. These words are the exact opposite of "lighted upon" and should be used depending on the situation.