A visor (also spelled vizor) is a surface that protects the eyes, such as shading them from the sun or other bright light or protecting them from objects.
Nowadays many visors are transparent, but before strong transparent substances such as polycarbonate were invented, visors were opaque like a mask with small holes to see and breathe through, such as:
- The part of a helmet in a suit of armor that protects the eyes.
- A type of hat consisting only of a visor and a way to fasten it to the head.
- Any such vertical surface on any hat or helmet.
- Any such horizontal surface on any hat or helmet (called a peak in British English).
- A device in an automobile that the driver or front passenger can lower over part of the windshield to block the sun (sun visor).
Some modern devices called visors are similar, for example:
Types of modern transparent visors include:
- The transparent or semi-transparent front part of a motorcycle crash helmet or police riotsquad helmets
- An eyeshield to protect the eyes from sunlight on an American football helmet
- A shield to protect the eyes from sunlight on a flight helmet or space suit
- Green eyeshades, formerly worn by accountants and others engaged in vision-intensive, detail-oriented occupations
Vizard Mask as Ladies Fashion Accessory 
The word vizard (sometimes visard) is used in Shakespearean English to refer to a visor, a mask, or a disguise (ex. "There, then, that vizard, that superfluous case, that hid the worse and show'd the better face." -- Love's Labors Lost V.ii.387)
Vizards were a fashion accessory for upper-class European ladies - gentlewomen - in the late 16th and into the 18th century. These light-weight masks were intended to protect a lady's face from sunlight while traveling in an open carriage, to preserve the (then) fashionable "look" of pale skin and rosy cheeks. This paleness contrasted with the sun-tanned skin of working-class women. Playwright William Shakespeare mentions this sun-adverse fashion craze in his play of 1590/91, Two Gentlemen of Verona (Act 4: Scene 4): "But since she did neglect her looking-glass; And threw her sun-expelling mask away, The air hath starved the roses of her cheeks; And pinched the lily-tincture of her face; That now she is become as black as I".
The Norwich Castle Museum in England has a rare surviving example of a lady's sun vizard. The plain (unadorned), oval-shaped mask covers the entire face, with two eye-holes and small opening at the mouth. It is made of black velvet, the inside lined with silk and stiffened with white paper; there is a glass bead attached to inside of the mouth opening, an aid to keeping the mask in place by gripping the bead with ones' teeth. The voluminous hairdos worn by ladies at this time prevented the mask from being secured by a ribbon tied around the head.
- Apollo 12 Image Library
- Ladies sun vizard cited in Shakespeare: Staging the World, Chapter 5, page 154; edited by Jonathan Bate & Dora Thornton (Oxford University Press: 2012)
- Castle catalogue discription of a velvet sun mask; accessed on-line 18 February 2013.