"living in the blood" (as a parasite does), by 1889, from Latin sanguis "blood" (see sanguinary) + colere "to inhabit" (see colony). Also, with classical stem, sanguinicolous.
Entries linking to sanguicolous
sanguinary adj.
1620s, "characterized by slaughter, attended by much bloodshed;" also bloodthirsty, eager to shed blood, delighting in carnage," from French sanguinaire or directly from Latin sanguinarius "of or pertaining to blood," also, rarely, "blood-thirsty," from sanguis (genitive sanguinis) "blood," a word of unknown origin. Latin distinguished sanguis, the generic word, from cruor "blood from a wound" (related to English raw, from PIE root *kreue-). The classical sense of "pertaining to blood" is rare in English.
colony n.
late 14c., "ancient Roman settlement outside Italy," from Latin colonia "settled land, farm, landed estate," from colonus "husbandman, tenant farmer, settler in new land," from colere "to cultivate, to till; to inhabit; to frequent, practice, respect; tend, guard," from PIE root *kwel- (1) "revolve, move round; sojourn, dwell" (source also of Latin -cola "inhabitant"). Also used by the Romans to translate Greek apoikia "people from home."
In reference to modern situations, "company or body of people who migrate from their native country to cultivate and inhabit a new place while remaining subject to the mother country," attested from 1540s. Meaning "a country or district colonized" is by 1610s.