reflex

Concise Oxford English Dictionary © 2008 Oxford University Press:
reflex/ˈriːfleks/

▶noun

• 1 an action performed without conscious thought as a response to a stimulus.

  ■ (in reflexology) a response in a part of the body to stimulation of a corresponding point on the feet, hands, or head.

• 2 a thing that reproduces the essential features or qualities of something else.

  ■ a word formed by development from an earlier stage of a language.

• 3 archaic a reflected source of light.

▶adjective

• 1 (of an action) performed as a reflex.

• 2 (of an angle) exceeding 180°.

• 3 archaic (of light) reflected.

• 4 archaic bent or turned backwards.

– derivatives
reflexly adverb.

– origin C16: from L. reflexus ‘a bending back’, from reflectere (see reflect).