Want unique words from a cell having multiple words separated by comma.

Sub remDup()
Dim dic As Object, cell As Range, temp As Variant
Dim i As Long
Cells(2, 3) = Range("A1") & " " & Range("A2")
Set dic = CreateObject("scripting.dictionary")
With dic
    For Each cell In Range("C1:C" & Cells(Rows.Count, "A").End(xlUp).Row)
        .RemoveAll
        If Len(cell.Value) > 0 Then
            temp = Split(" " & cell.Value, ",")
            For i = 0 To UBound(temp)
                If Not .Exists(temp(i)) Then .Add temp(i), temp(i)
            Next i
            cell.Value = Mid(Join(.Keys, ","), 2)
        End If
    Next cell
End With
       
End Sub

Option Explicit
    
Function UNIQUES(ByVal CellRange As Range) As String
Static DIC      As Object 'Dictionary
Dim Cell        As Range
Dim CellString  As String
Dim aryStrings  As Variant
Dim n           As Long
    
    If DIC Is Nothing Then Set DIC = CreateObject("Scripting.Dictionary")
    
    DIC.RemoveAll
    For Each Cell In CellRange
        CellString = Cell.Value
        If InStr(1, CellString, ",") > 0 Then
            aryStrings = Split(CellString, ",")
            For n = LBound(aryStrings, 1) To UBound(aryStrings, 1)
                DIC.Item(Trim(aryStrings(n))) = Empty
            Next
        Else
            DIC.Item(Trim(CellString)) = Empty
        End If
    Next
    
    If DIC.Exists(vbNullString) Then DIC.Remove (vbNullString)
    
    If DIC.Count > 1 Then
        UNIQUES = Join(DIC.Keys, ", ")
    ElseIf DIC.Count = 1 Then
        '// To get past an anomaly of late-bound DIC, as we cannot use DIC.Keys(0)  //
        aryStrings = DIC.Keys
        UNIQUES = aryStrings(0)
    Else
        UNIQUES = "No Vals"
    End If
End Function