sanguinolent

SYLLABICATION: san·guin·o·lent
PRONUNCIATION: sng-gwn-lnt
ADJECTIVE: Mixed or tinged with blood.
ETYMOLOGY: Latin sanguinolentus, full of blood : sanguis, sanguin-, blood + -olentus, abounding in.
GENERALITIES. ► Œdematous swellings, like elephantiasis. ► Infiltration of bloody serum, equally diffused throughout the substance of the cellular tissue, but better marked in the vicinity of the bites. ► Very extensive suppuration. ► Suppuration and sero-sanguinolent infiltration of all the tissues

The onset of gas gangrene may occur between 1 and 6 hours after injury and presents with severe and sudden pain in the infected area. The skin overlying the wound in the early phases appears shiny and tense and then becomes dusky and progresses to a bronze discoloration. The infection can advance at a rate of 6 inches per hour. Any delay in recognition or treatment may be fatal. Hemorrhagic bullae or vesicles may also be noted. A thin, sero-sanguinolent exudate with a sickly, sweet odor is present. Swelling and edema of the infected area is pronounced. The muscles appear dark red to black or greenish, are noncontractile, and do not bleed when cut.

You could go for the explanatory approach... it doesn't sound too much like layman's language.