Here are the possible solutions for staircase surface clue
Answer
Clue
Relevancy
step
Clue
Staircase surface
lance
Clue
Army surface-to-surface missile
Definition
to pierce with a spearlike weapon
routine
Clue
Dive, surface, dive, surface, etc.?
touchpad
Clue
Microsoft Surface surface
any
Clue
"... card, ___ card" (Last week: The two diagonally hidden 18-letter titles were "Up the Down Staircase" and "Upstairs, Downstairs." The latter answer turned downward at the D of "Downstairs.")
