What's the opposite of a turnbuckle?

A turnbuckle works under tension - it draws two opposite-threaded rods closer together by screwing them into a central barrel.

What is the name of a device that has a central rod, left-hand threaded on one end and right-hand threaded on the other end, which works under compression to force two nuts apart symmetrically?

Wouldn’t that just be a turnbuckle that you turned the other way?

A Screwjack

The ends would need to be different.

deturnbuckle

Thats why wielders were invented.

Do they wield welders?
I think the answer is jackscrew.

Crap.

Winner.

Stranger

It’s called an “elkcubnrut”.

AKA JackScrew it’s most common name.

A turnbuckle has one RH threaded end and one LH threaded end.