acompañante

n. attendant; escort, man who accompanies a woman (on a date, to a dance, etc.); squire

= chaperon, accompanying person.
Ex: Apart from the tale that babies are found under gooseberry bushes, to 'play gooseberry' was to act as a chaperon, or be an unwanted third presence when lovers wanted to be alone.
Ex: Patients who attended with a spouse/partner/carer/family member indicated it was helpful to them and the accompanying person.
----
* instrumento acompañante = accompanying executant.
* servicio de acompañante = escort service.
* viajar de acompañante = ride + shotgun.