blind

Blind means the eyes do not work — no sight at all, or so little that it makes no difference. A white cane tapping along the kerb; a dog gone blind in one eye that still finds its bowl.

Say blind people, or a person who is blind, and leave the blind as a group noun alone, because that use has gone out of favour. From the eyes the word stretches to mean without information: a blind corner is one you cannot see round, a blind spot is what the mirror misses and also the subject you never notice you get wrong, a blind date is a date with someone you have not met. Blinds, in the plural, are the slatted things you pull down over a window, and as a verb, headlights blind you for a second. To turn a blind eye is to see the wrong thing and decide not to act. Blind drunk means very drunk indeed.

Phrases it lives in

• turn a blind eye — notice something wrong and deliberately do nothing about it
• blind spot — an area you cannot see, or a subject you consistently misjudge
• the blind leading the blind — someone with no more knowledge than you trying to guide you