HH8

HH8, HH-8, HH 8, HH.8, may refer to:


 * Echoes of Honor (novel), abbreviated "HH8", eighth main-line novel in the Honor Harrington novel series, part of the Honorverse fictional milieu created by David Weber


 * HH8, one of the Hamburger–Hamilton stages in chick development
 * KiSS1-derived peptide receptor (HH8)