The gate on the northern side and the gate on the southern side represent the two ears, and the two gates facing the western side represent the rectum and the genitals. All the doors and gates are described below

Expressions researched:
"The gate on the northern side and the gate on the southern side represent the two ears, and the two gates facing the western side represent the rectum and the genitals. All the doors and gates are described below"

Srimad-Bhagavatam

SB Canto 4

Of the seven doors on the surface—namely the two eyes, two ears, two nostrils and one mouth—five look forward, and these are described as the doors facing the eastern side. Since looking forward means seeing the sun, these are described as the eastern gates, for the sun rises in the east. The gate on the northern side and the gate on the southern side represent the two ears, and the two gates facing the western side represent the rectum and the genitals. All the doors and gates are described below.

SB 4.25.46, Translation and Purport

My dear King, of the nine doors, five led toward the eastern side, one led toward the northern side, one led toward the southern side, and two led toward the western side. I shall try to give the names of these different doors.

Of the seven doors on the surface—namely the two eyes, two ears, two nostrils and one mouth—five look forward, and these are described as the doors facing the eastern side. Since looking forward means seeing the sun, these are described as the eastern gates, for the sun rises in the east. The gate on the northern side and the gate on the southern side represent the two ears, and the two gates facing the western side represent the rectum and the genitals. All the doors and gates are described below.