When adding keywords to "Keyword Picker" attributes using the '[edit keywords]' under Admin > Attributes > Manage attributes, you can import keywords from an external file.

After clicking on the 'Import keywords from a file' link follow the instructions on the page and use the sample import file as a starting point for your import.

Alternatively, if you regularly need to import a keywords file you can use the "Keyword Import URL" property when editing the Keyword Picker attribute.
The system will then import keywords from the remote file every 60 minutes. If you would like to change the polling period please contact our Customer Support Team.

NB: If you are importing hierarchical keywords into a Keyword Picker attribute:

If you are importing a hierarchical keyword taxonomy (instead of using the simple Name/Synonym setup above) Asset Bank requires a delimiter to be set between the Parent and Child keywords.

The default delimiter is a forward slash '/' but it is worth checking what is used on your site before importing keywords from a file, as some custom configurations use a pipe '|' or other characters.

Here is an example of a hierarchical keyword string using a forward slash:
Nature & environment/Bodies of water/Oceans/Arctic Ocean