The phrase "made plain" means to make something clear and easily understandable. Some synonyms of the phrase are "clarified," "explained," "simplified," "elucidated," and "deciphered." Other synonyms include "unveiled," "uncovered," and "revealed." The idea behind all of these words is to remove any confusion or ambiguity that may exist, and to make something easy to understand. By using these synonyms, you can bring more clarity to your communication and help ensure that your message is well-received. So, whether you are giving a presentation or having a conversation, using one of these synonyms can help you get your point across more effectively.