Noun

(en noun)

A person with extensive knowledge or ability in a given subject.

* If an expert''' says it can't be done, get another '''expert . -

* {{quote-magazine, date=2013-07-20, volume=408, issue=8845, magazine=(The Economist)

, title= Welcome to the plastisphere , passage=Plastics are energy-rich substances, which is why many of them burn so readily. Any organism that could unlock and use that energy would do well in the Anthropocene. Terrestrial bacteria and fungi which can manage this trick are already familiar to experts in the field.}}

(chess) A player ranking just below master.

Noun

(en noun)

A beginner; a person who is new to a subject, skill, or belief.

A novice (recent convert), a new convert or proselyte, a new monk.

(Christianity) A name given by the early Christians, and still given by the Roman Catholics, to those who have recently embraced the Christian faith, and been admitted to baptism, especially those converts from heathenism or Judaism.

(biology) A plant species recently introduced to an area (in contrast to archaeophyte, a long-established introduced species).