Definitions of ulterior:

• adjective:   beyond or outside an area of immediate interest; remote

  Example: "A suggestion ulterior to the present discussion"

• adjective:   lying beyond what is openly revealed or avowed (especially being kept in the background or deliberately concealed)

  Example: "Looked too closely for an ulterior purpose in all knowledge- Bertrand Russell"

• adjective:   coming at a subsequent time or stage

  Example: "Without ulterior argument"