Navigate to the Central Administration. Click on Application Management. Click on Manage service applications which is available under Service Applications. Click on MMS (Managed Metadata Service). Expand MMS termstore in the Taxonomy Term Store where all the groups for that particular termstore will be displayed. In this blog you will see how to delete the group from the term store.

Steps Involved:

1. Open Visual Studio 2012 (Run as administrator).

2. Go to File=> New => Project.

3. Select Console Application in the Visual C# node from the installed templates.

4. Enter the Name and click on Ok.

5. In the solution explorer, right click on References folder and then click on Add Reference.

6. Add the following assemblies from 15 hive (C:\Program Files\Common Files\microsoft shared\Web Server Extensions\15\ISAPI).

a. Microsoft.SharePoint.Client.dll

b. Microsoft.SharePoint.Client.Runtime.dll

c. Microsoft.SharePoint.Client.Taxonomy.dll

7. Open Program.cs file and replace the code with the following 

 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.SharePoint.Client;
using Microsoft.SharePoint.Client.Taxonomy;
using System.Collections.ObjectModel;
 
namespace ManagedMetadataClient
{
    class Program
    {
        static void Main(string[] args)
        {
            // ClienContext - Get the context for the SharePoint Site 
            // SharePoint site URL - http://c4968397007/
            ClientContext clientContext = new ClientContext("http://c4968397007/");
 
            // Get the TaxonomySession
            TaxonomySession taxonomySession = TaxonomySession.GetTaxonomySession(clientContext);
 
            // Get the term store by name
            TermStore termStore = taxonomySession.TermStores.GetByName("MMS");
 
            // Group GUID
            Guid guid = new Guid("1e6de19d-32db-4a86-86b2-0767658f9b08");
 
            // Get the term group using GUID
            TermGroup termGroup = termStore.GetGroup(guid);
 
            // Delete the term group
            termGroup.DeleteObject();
           
            // Execute the query to the server
            clientContext.ExecuteQuery();
           
        }
    }
}

[Note: Site Collection http://c4968397007/ is associated with MMS service application].