As hill next to point and line on map (7)
I believe the answer is:
equator
'line on map' is the definition.
'equator' can be an answer for 'line' (equator is a kind of line). I'm not sure about the 'on map' bit.
'as hill next to point' is the wordplay.
'as' becomes 'qua' ('qua' is a Latin term meaning 'in the capacity of').
'hill' becomes 'tor' (tor is a kind of hill).
'next to' says to put letters next to each other.
'point' becomes 'E' (compass point).
'qua'+'tor'='quator'
'quator' after 'e' is 'EQUATOR'.
'and' acts as a link.
Can you help me to learn more?
(Other definitions for equator that I've seen before include "Line through Brazil, Kenya, Sumatra" , "Line around earth equidistant from poles" , "Imaginary line around the earth's circumference" , "The great circle" , "Earth's north-south dividing line" .)