A is for..........

Argon - Argon is an inert, colorless, odorless gas.  It has lower heat conduction properties than air.  If the air in between 2 panes of glass in a double insulated glass unit or thermal pane is replaced with argon, the windopw's energy efficiency is enhanced.  Argon gas is usually used in combination with low E.

Astragal - Not a female space shuttle pilot..........An Astragal is a vertical wood piece attached to the edge of one window sash which closes the other sash when it closes. Part of a window frame. Specifically a strip, usually of wood or metal, separating two panes of glass.

Awning window - The awning window is a window style with an outward swinging sash.  It is usually to hinged.  It is usually wider than it is tall.