The term 'not false' can be represented by three words in a crossword puzzle: TRUE (4 letters), LOYAL (5 letters), and SINCERE (7 letters). TRUE is an adjective that means in accordance with fact or reality. LOYAL is an adjective that means having or displaying faithfulness to commitments or obligations. SINCERE is an adjective that means free from pretense, deceit, or hypocrisy. Together, these three words represent the concept of not false, which implies honesty and trustworthiness.