novocaine. A synthetic local anesthetic.

noxious. Injurious; harmful.

nucleus. The essential part of a typical cell and the controlling centre of its activity.

O

obliteration. Extinction.

official (in pharmacy). Authoritative; standard.

oid. Like, as in lymphoid, resembling or like lymph.

oil. A liquid of fatty consistency, insoluble in water and inflammable. Examples: camphorated oil, carbolic oil, carron oil, linseed oil, oil of turpentine, sweet oil, sesame oil, tar oil.

ointment. A soft, fatty, medicated mixture.

onychauxis. Enlargement of finger or of toe nails.