Y
y-axis See axis, anteroposterior.
y sutures of the lens See lens sutures.
yag laser See laser, neodymium-yag.
yellow One of the hues of the visible spectrum evoked by stimulation of the retina by wavelengths situated in a narrow region between about 560 and 590 nm, i.e. between red and green. The complementary colours to yellow are blues.
yellow spot See macula lutea.
yellow vision See xanthopsia.
yoke muscles See muscles, yoke.
Young’s experiment See experiment,
Young’s.
Young’s modulus of elasticity See modulus of elasticity.
Young’s optometer See optometer, Young’s.
Young-Helmholtz theory See theory,
Young-Helmholtz.
