Tailstock n. : The sliding block or support, in a lathe, which carries the dead spindle, or adjustable center. The headstock supports the live spindle.

Example:
when using a face plate and Tailstock on a lathe:?

Taxonomy
Tailstock, workpiece, free encyclopedia, wood-turning lathe, search, Personal tools, engineering, conjunction, reaming, tools, hole, Interaction, Toolbox, non-profit organization, metalworking, Machine tools, rotary table, milling machine.

Defination from the web:
tailstock is a device often used as part of an engineering lathe, wood-turning lathe, or used in conjunction with a rotary table on a milling machine. ... A tailstock is particularly useful when the workpiece is relatively long and slender. ...