Recreational vehicle held by signal leading to bend (5)
I believe the answer is:
curve
'bend' is the definition.
(curving is a kind of bending)
'recreational vehicle held by signal' is the wordplay.
'recreational vehicle' becomes 'RV' (abbreviation).
'held by' means one lot of letters goes inside another.
'signal' becomes 'cue' (as in an actor's cue).
'rv' inserted within 'cue' is 'CURVE'.
'leading to' acts as a link.
(Other definitions for curve that I've seen before include "Line on a graph" , "No part of this line is straight" , "way of learning" , "Arch" , "Wind" .)