(medicine) A disorder of porphyrin metabolism in which uroporphyrin and coproporphyrin are present in the tissues and urine.

plural of Ortokid

(linguistics, phonetics) A consonant articulated by the lips. / (music) An organ pipe having a lip that influences its sound. / (zootomy) Any of the scales bordering the mouth opening of a reptile.

(baseball) The frequency with which a hitter successfully reaches first base.