There are seven distinct words in my unabridged dictionary:

 

buckskin

buckskinned

buckskins

crackskull

thickskin

thickskull

thickskulled

 

My VB program found them in 1 second:

 

Imports System
Imports System.IO
Imports System.Text
Imports System.Runtime.InteropServices
Imports System.Math
Module Module1
    Sub Main()
        Randomize()
        Dim strstarttime As String
        Dim strendtime As String
        Dim strend As String
        strstarttime = TimeOfDay
        Console.WriteLine( _
        TimeOfDay & ": Start of execution.")
        lookforcksk()
        Console.WriteLine("Start of execution: " & strstarttime)
        strendtime = TimeOfDay
        Console.WriteLine( _
        TimeOfDay & ": End of execution.")
        strend = "?"
        Console.WriteLine(" ")
        While strend <> "x"
            Console.WriteLine( _
            "Please enter X to exit program.")
            strend = LCase(Console.ReadLine())
        End While
    End Sub

    Sub lookforcksk()
        Dim strline As String
        Dim objStreamReader As StreamReader
        strline = " "
        objStreamReader = _
        New StreamReader("C:\VBWORDLIST.MASTER")
        Do While Not strline Is Nothing
            strline = objStreamReader.ReadLine
            strline = LCase(strline)
            If strline <= " " Then
                Exit Do
            End If
            If strline Like "*cksk*" Then
                Console.WriteLine(strline)
            End If
        Loop
        objStreamReader.Close()
    End Sub
End Module