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A Guide to Omni

A guide to Omni, an academic search tool that gives you access to information resources from McMaster and other participating Ontario university libraries.

Boolean - AND,OR, NOT, ( )

Boolean operators allow search words to be combined.

AND (all words), OR (any words), and NOT (excludes words) are supported in Omni.

The AND operator is the default operator which means that if there is no Boolean operator specified between words, the AND operator is used and Omni will search for all the words.

In Omni, Boolean operators are case-sensitive and must be entered ALL CAPS (i.e., uppercase letters). Search words are case-insensitive.


• stocks bonds finds items containing both words, in any order
• stocks AND bonds finds items containing both words, in any order
• stocks OR bonds finds items containing either word, in any order
• stocks NOT bonds finds items containing the first word, but not the second word

When using multiple Boolean operators in a single search string, use brackets/parentheses (  ) to ensure search words are combined and processed in the order intended. 

Without brackets, search words will automatically be processed from left to right. The AND and NOT operators will be processed before the OR operator.


Without brackets: shakespeare AND tragedy OR sonnet
Finds items that contain both the words Shakespeare and tragedy plus items containing the word sonnet on its own.

To change the default order of precedence, place brackets around words using the OR operator so that anything enclosed within brackets is processed first.


With brackets: shakespeare AND (tragedy OR sonnet)
Finds items that contain the word Shakespeare with either the words tragedy or sonnet.

Phrases - "Quotation Marks"

Put quotation marks "  " around search words to find items containing the exact words in the order specified.


• "cancel culture"
• "roaring twenties"
• "great lakes"
• "to be or not to be"

If a phrase is not enclosed with quotation marks, Omni will find items that contain the individual words in the phrase, regardless of whether these words are located next to each other in the order specified.

If a comma is used to separate words in a list, the comma must be followed by a space. Otherwise, Omni will consider the comma to be part of the word and return fewer results than expected.

Wildcards - ? and *

A wildcard symbol (or truncation symbol) can be used in a search to find multiple variations of a word.

The following wildcard symbols are supported in Omni:

  • The question mark ? replaces a single character (1) anywhere in the word.
  • The asterisk  *  replaces any number of characters (0 or more) and can be used in the middle or at the end of a word.  


• wom?n finds items containing woman, women, womin, womyn, etc.
• te?t finds items containing tent, test, text, etc.
• te*t finds items containing tent, test, text, tempt, tenement, testament, , etc.
• environment* finds items containing environment, environmental, environmentalist, environmentalism, etc.
• manag* finds items containing manage, manages, manager, managers, managing, management, etc.
• ? finds most (if not all) items

Automatic Search and Expansion

Omni will sometimes automatically include additional related terms to your search. Once a term is entered and a search is initiated, an option to limit by the specific term entered will appear.

NOTE: This feature only works in the first two search scopes - McMaster + Other Omni Libraries and McMaster Libraries (Catalogue & Articles+)


  • supply chain management also retrieves business logistics
  • public policy also retrieves political planning
  • heart attack also retrieves myocardial infarction
  • ADHD also retrieves attention deficit hyperactivity disorder

Automatic Search and Expansion in Omni

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