Young-Helmholts theo

(yung-helm’holts) [Thomas Young, English physician, 1773-1820; H. L. Ε. Helmholts, German physician of the roth century]. See theory. Young’s operation (yungz) [Hugh H. Young, Baltimore surgeon]. See under operation. Young’s rule (yungz) [Thomas Young, English physician, 1773-1829]. A rule for determining the proportion of an adult dose to give to a young child, consisting in adding 12 to the age and dividing by the age, which will give the denominator of a fraction whose numerator is 1. Thus, for a child three years old, 3+ = 5, so that the dose for the child is one-fifth of the adult dose. ypsiliform (ip-sil’if-orm) [Gr. ὑψιλόν the letter u or y.] Y-shaped. y.s. Abbreviation for yellow spot of the retina.