gee string

noun3

1. •
   The right hand or off side rein on a team of horses, mules, bullocks etc

   • a ten-in-hand bull team came down South A street .... The off bull on the "gee" string bowed his glossy neck and champed his bit impatiently, — 1877
2. •
   Line or rope connecting dog-team to sled

   • The gee string (rope by which dog team is attached to front of sled) is then unsnapped — 1909
3. •
   Chin strap of a hat

   • There are a few men that wear their pistols exposed for the same reason that some wear diamond breast pins, or a cowboy hat with a gee-string hanging down the back of his neck. — 1885