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D7 - Working with Structure - Taxonomy - Vocabularies - Edit Vocabulary - Click Edit Vocabulary Link

1. Open Vocabulary for Editing

From the Taxonomy landing page...

Locate the vocabulary you wish to edit and click its corresponding Edit Vocabulary link.

D7 - Working with Structure - Taxonomy - Vocabularies - Edit Vocabulary - Vocabulary Scren Open for Editing

2. Vocabulary Edit Form

The vocabulary edit screen will appear.

Please note that changing the name of the vocabulary isn't typically a problem, but changing the machine name could have some negative effects if the vocabulary is being used anywhere in the site.