In the year 2010, I got an opportunity to hear Dr David Maister, co-author of The Trust Advisor in a conference in Washington DC, USA. Since then, the collocated word, Trusted-Advisor got stuck with me, and is also an often-aspired phrase in the service industry.
We use many collated words in our personal and professional life, like Manager-Employees, Employer-Employee, Dealer-Distributor, Market-Customer, etc. One can notice a common thread in all of these. Often the word of high prominence and significance is mentioned and spoken first in all these collocated words. You just cannot speak other way around, so much is the significant of the first word.