1) Architectural element 2) It helps support a structure 3) Type of Truss bridge 4) Vertical tie in a roof truss 
A queen post is a tension member in a truss designed to span longer openings than a king post truss. A king post uses one central supporting post, whereas the queen post truss uses two. Even though it is a tension member, rather than a compression member, they are commonly still called a post. A queen post is often confused with a queen strut, one...
A roof truss having two vertical posts between the rafters and the tie beam; the upper ends of the vertical posts are connected by a straining piece (such as a tie rod or cable).
a pair of vertical timbers rising from a tie beam to support purlins. See roof. 
Queen'-post` noun [ Arch.] One of two suspending posts in a roof truss, or other framed truss of similar form. See King-post . 
[n] - vertical tie post in a roof truss
noun vertical tie post in a roof truss
either of a pair of timbers or posts extending vertically upward from the tie beam of a roof truss or the like, one on each side of the center.