Adviser

An adviser or advisor is normally a person with more and deeper knowledge in a specific area and usually also includes persons with cross-functional and multidisciplinary expertise. An adviser's role is that of a mentor or guide and differs categorically from that of a task-specific consultant. An adviser is typically part of the leadership, whereas consultants fulfill functional roles.^[1]

The spellings adviser and advisor have both been in use since the 16th century.^[2] Adviser has always been the more usual spelling, though advisor has gained frequency in recent years and is a common alternative, especially in North America.^[3]^[4]

^ Definition agreed on by both professional advisors and consultants in business magazine along with functional workflow graphic."The Difference Between Consultants and Advisors"
^ Oxford English Dictionary, s.vv. "adviser" and "advisor" (subscription required).
^ Google Ngram Viewer, "adviser, advisor".
^ Oxford Dictionaries, s.v. "adviser".

[1] Definition agreed on by both professional advisors and consultants in business magazine along with functional workflow graphic."The Difference Between Consultants and Advisors"

[2] Oxford English Dictionary, s.vv. "adviser" and "advisor" (subscription required).

[3] Google Ngram Viewer, "adviser, advisor".

[4] Oxford Dictionaries, s.v. "adviser".

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