Crossword clues for the word: MAINIDEA The word MAINIDEA has appeared as an answer to at least 8 crossword clues on different crossword puzzles. Crossword clues for MAINIDEA Showing 1 to 8 of 8 results Clue(s) "Theme, e.g." Central thrust Essay's central thesis: 2 wds. Gist Presentation at the start of a five-paragraph essay Theme Thesis statement Walt Whitman's core concept?