Recently I ran into an interesting discovery regarding the features in Office 2013 Dictionary. Note that the Dictionary feature includes the following actions in Office: Define and Synonyms.
Starting with Office 2013, an independent Office Store account and an internet connection are required to leverage these functions. Microsoft is treating this feature as a web application, since you have multiple choices when selecting a dictionary. This means that if a computer is not connected to the internet these features will not function. This is a change for Microsoft, and points users in the direction of the Office Live platform.
I did some research into working around this and found that this is a built-in feature. There is no manageable workaround. In the end, this feature is as-designed by Microsoft for Office 2013, and it will require logging into the Microsoft Office Store. For the time being, there does not seem to be a method to bypass the Office Store and the required Office Store or Office 365 account.
Our suggestion for those interested in this feature is for users to create a Microsoft account via the wizard in Office Suite, or for firms to configure Office 365 synchronization for accounts so that users may authenticate to the Office Store using their domain accounts.
Here is a link from Microsoft on installing the Office 2013 Dictionary in Word.