Truncation is the act or process of shortening or reducing something. In the context of literature searching, it refers to the shortening of a search term so as to bring up words that share a root word but have different endings. Truncation is a technique frequently used in keyword searching, in which it helps reduce the number of variations you have to search on separately.
For example:
This truncated Word ... | Will bring up the following: |
child* | child childhood childlike children childrens childs |
gene* | gene genes genetic genetically geneticist geneticists genetics |
hospital* | hospital hospitals hospitalise hospitalised hospitalize hospitalized hospitalisation hospitalización hospitalization |
nurs* | nurse nursery nurseries nurses nursing |
In most databases, the truncation symbol is the asterisk (*), though it may be any character designated by the database. Check the database's Help pages for details.
A related technique is the use of wildcards, in which a character (often the asterisk) may be substituted for zero or more letters within the interior of a word. It is useful in the case of alternative spellings, e.g., tumo*r, to bring up both tumor and tumour. Again, check the database's Help pages for details.