Correct perspective for seeing something trigonometrical (5,5)
I believe the answer is:
right angle
'seeing something trigonometrical' is the definition.
I can't tell whether this defines the answer.
'correct perspective' is the wordplay.
'correct' becomes 'right' ('right' can be a synonym of 'correct').
'perspective' becomes 'angle' (angle is a kind of perspective).
'right'+'angle'='RIGHT-ANGLE'
'for' is the link.
Can you help me to learn more?
(Other definitions for right angle that I've seen before include "Ninety degrees" , "That between perpendicular and base" , "Ninety degree corner" , "a good number of degrees?" , "corner of the square" .)