Neckerchief n. : A kerchief for the neck; -- called also neck handkerchief.

Example:
What are the Neckerchief slide / woggle looking things that cowboys or texans wear called?

Taxonomy
neckerchief, neckerchief slide, colours, troop, Scouting, free encyclopedia, scarf, plaid, triangle, neck, slip knot, woggle, wearer, Scout Troop, reef knot, square knot, enlisted sailors, Scouting tradition.

Defination from the web:
neckerchief (Also known as a Scarf in parts of England) is a type of neckwear associated with Scouts and sailors. ... Either neckerchief is then placed on the wearer's back, under or over the shirt collar with the ends at the front of the wearer. ...