Definition of knell. 1  transitive verb. : 2  to summon or announce by or as if by a knell. 3  intransitive verb. 4  1 : to ring especially for a death, funeral, or disaster : toll. 5  2 : to sound in an ominous manner or with an ominous effect.
For the journal, see Demography (journal) . Demography is the statistical study of populations, including of human beings. As a very general science, it can analyze any kind of dynamic living population, i.e., one that changes over time or space (see population dynamics).
Someone whos studies volcanoes is called a volcanologist or *quote:(A volcanologist is a person who studies the formation of volcanoes, and their current and historic eruptions.). While someone who studies snakes is called a Ophiologist. [The simpler answer is like this.