Here are the possible solutions for spiral staircase essentially clue
Answer
Clue
Relevancy
helix
Clue
Spiral staircase, essentially
Definition
(Greek) something spiral in form
banister
Clue
It spirals down a spiral staircase
Staircase upright
Definition
a stair handrail
caracole
Clue
Spiral staircase
Definition
(French) to perform a half turn on a horse, also CARACOL
newel
Clue
Spiral-staircase pillar
Definition
a post supporting the handrail of a staircase
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.")