1998 Lexus ES 300 Rear suspension arm

Suspension problem
1998 Lexus ES 300 6 cyl Front Wheel Drive Automatic 250k miles

I need to order a rear L and R rear adjustable suspension arm. Unfortuately I don't know what it's called. Is It a Trailing Arm? A control Arm? A Toe Arm? I is the furthest to the back of the car and has a turnbuckle type adjustment on it. The rods a fine however the bushing are shot and I am getting a wobble when I drive. Any Ideas?

Thanks,
David