The term "surreptitiousnesses" refers to the act of being secretive, sneaky or furtive. The antonyms for this word would then describe actions that are open, transparent or honest. Some potential antonyms for this adjective include overt, candid, straightforward, truthful, sincere and straightforward. These antonyms would describe someone who is forthcoming with information and who acts in a way that is not intended to hide or deceive. By using the opposite of surreptitiousnesses, we can accurately describe someone who is forthright and honest in everything they do, which is a trait that is highly prized in many areas of life.