Green’s Dictionary of Slang

hog-eye n.

also hog’s eye
[supposed resemblance]

1. [1900s] (US) a hamlet or small village.

2. [1910s+] (US) the female genitals.

3. attrib. use of sense 2.

4. [1930s] (US prison) a skeleton key.

5. [1930s+] (US Und.) a lock.

6. [1990s+] the urethral hole in the head of the penis.

In compounds

hog-eye man (n.)

[mid–late 19C] (US) a sailor, often black, who manned the ‘hog-eye boats’, running between Cape Horn and San Francisco at the time of the Calif. Gold Rush; as underlined in popular rhymes, such men had a reputation for sexual adventuring and prowess.