「Leather centrally」as a MARTINGALE, the leather「…strap of a horse's harness that connects the girth to the noseband and is designed to prevent the horse from throwing back its head」
　　[　https://www.thefreedictionary.com/martingale　]　
　If a horse throws back its head, a rider will often be knocked from the mount and the horse will run away. This leather strap connects the bridle to the girth strap under its belly, positioned below the neck (not above it, as suggested by the given meanings). Used as a PREVENTIVE MEASURE THAT RESTRICTS MOVEMENT when an animal is DISCONTENTED, UNHAPPY by adding a FETTER, SHACKLE to its head and neck.
　A strap positioned above a neck, as suggested by the given meanings, used as a PREVENTIVE MEASURE THAT RESTRICTS MOVEMENT causing a person to be DISCONTENTED, UNHAPPY by adding a FETTER, SHACKLE to its head and neck refers to a device used to prevent access to the person fondling his or her genitals, what in the West was known as a CHASTITY BELT or CHASTITY HARNESS.
　「Leather with vulva inspection」prior to any foot dis-integrating was used for the same purpose, a PREVENTIVE MEASURE THAT RESTRICTED MOVEMENT when a captured person was DISCONTENTED, UNHAPPY by adding a FETTER, SHACKLE to the head and neck, and likely to other areas of the body since no one enjoys being kicked in the face, and least of all while bending down to closely examine a vulva.
　「Skin of the central vulva, the hymen」the sought-for HYMEN also acted as a type of FETTER or SHACKLE and a PREVENTIVE MEASURE THAT RESTRICTED MOVEMENT, since no one could have sex with her vagina until after the lord, who had purchased her from her family, had first performed the deflowering procedure. Note the left elements are「covering over cavity middle of vulva, full from top to bottom left to right」or「bastards have been on vulva and screwing.」

Modern definitions (that generally disregard history) …excluding politically incorrect concepts and other meanings deemed offensive today; may list only pigeonholed definitions, euphemisms, or meaningless mnemonics)
Chinese: martingale (leather strap in horse harness); discontented
Japanese: martingale, discontented, unhappy
Unihan extended: leather strap over horse's neck
EDRDG: martingale; breast harness; saddle girth; fetter; shackle; carry on back