Length of a bridge (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
span
'length of a bridge' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for span that I've seen before include "Stretch < fresh" , "Width of pans" , "Interval in terms of time" , "Width of wings" , "Bridge - spick and ___" .)