Macrocephaly Relative macrocephaly SNOMEDCT_US:3961000119101 HP:0000257 HP:0001364 Macrocephaly, relative Relatively large head UMLS:C1849075 HP:0004482 A relatively mild degree of macrocephaly in which the head circumference is not above two standard deviations from the mean, but appears dysproportionately large when other factors such as body stature are taken into account. Disproportionately large head