Bombay Screw
An earring fitting where the post itself is threaded, and a small screw back winds directly onto it.
The thread is cut into the post, so the back grips the post rather than a separate stem.
It gives a slim, discreet finish, which suits lighter and more contemporary pieces where a wide disc would be visible from the side.
It is the common fitting across North and West India, and the counterpart to the Madras screw in the South.
What you will hear
“Bombay screw and Madras screw are just two names for a screw back.”
In fact: They are different fittings. Bombay screws thread on the post; Madras screws use an unthreaded stem with a disc that twists on. Backs are not interchangeable between them.
When you are buying
Good for light studs taken on and off often. The threads are fine, so wind gently and stop at resistance, since a crossed thread on a gold post is an expensive repair.
Madras Screw
A South Indian earring fitting: a short rounded post through the ear, with a disc-shaped screw that twists onto the stem behind it.
Screw Back
An earring post with a threaded end and a nut that screws on. The most secure earring fastening.
Stud
An earring that sits directly on the lobe, held by a post through the piercing.
Ear Wire
The hook that passes through the piercing on a hanging earring.