16 across
Looking
west,
this
elevated
point
used
to
measure
height
and
circumference
(5)
Looking west, this elevated point used to measure height and circumference (5)
hints
0
checks
0
hints
The definition is at the end of the clue.
How the clue works
The answer is circumference, meaning GIRTH. Take TRIG, an elevated survey point used to measure distances, and read it westwards (backwards in an across clue) to get GIRT, then add H for "height". Together that spells GIRTH.