ulterior

(s) lying beyond what is openly revealed or avowed (especially being kept in the background or deliberately concealed)
- subterranean motives for murder
- "looked too closely for an ulterior purpose in all knowledge"- Bertrand Russell
subterranean, subterraneous,
(s) beyond or outside an area of immediate interest; remote
- a suggestion ulterior to the present discussion
- "without...any purpose, immediate or ulterior"- G.B.Shaw
(s) coming at a subsequent time or stage
- without ulterior argument
- the mood posterior to
later, posterior,

subterranean subterraneous later posterior

ulteriority ulteriorly