not openly; inwardly; "they were secretly delighted at his embarrassment"; "hoped secretly she would change her mind"
in secrecy; not openly; "met secretly to discuss the invasion plans"; "the children secretly went to the movies when they were supposed to be at the library"; "they arranged to meet in secret"
the eye unaided by any optical instrument that alters the power of vision or alters the apparent size or distance of objects; "it is not safe to look directly at the sun with the naked eye"
increased pressure in the eyeball due to obstruction of the outflow of aqueous humor; damages the optic disc and impairs vision (sometimes progressing to blindness)