Does having anosmia mean that you have completely lost your sense of smell?

Yes: The term itself does mean that there is an absence of the sense of smell. Hyposmia is a diminished sense of smell. Some cases are secondary to nasal obstruction due to allergy, deviated septum with hypertrophic turbinates. A viral infection may injure the olfactory nerve twigs in the superior part of the nose. Very, very rarely a tumor of the base of the frontal lobe may be the cause.