Compact Bone. Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix.Between the rings of matrix, the bone cells (osteocytes) are located in spaces called lacunae.ompact Bone. Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix.
LEFTenant is the way British troops pronounce the rank Lieutenant. The two words mean different things within different military groups, but there is no actual difference. A British troop can refer to an American Lieutenant as  leftenant and not be incorrect.
Something that is an accessory to something but not an integral part of it is an appurtenance. If you buy a car, you may want to purchase a few appurtenances for it, like an ice scraper and fuzzy dice to hang from your rear view mirror. The noun appurtenance does not only refer to tangible objects, such as appurtenances of a certain lifestyle. It can also mean equipment or gear for a certain task. By the time you fill your locker with all the appurtenances of a high school student, you won't have room for a coat.