I am struggling on how to say when someone is an expert on a certain topic or skill. Because it is not exactly the meaning I intend to give.
What I really want to say is like: "When you want to know about IT, ask John. He is the __________ in this topic within our group".
Can I use the word "reference" to fill in the blank? is that usual?
Thanks everyone.
You cannot use "reference" to fill in the blank here.
"When you want to know about IT, ask John. He is the ___ in this topic within our group".
But you can "refer" to this person, who is an ___ in this topic.
A formal and most commonly used word would be:
Expert — ODO
A person who is very knowledgeable about or skilful in a particular area
"an expert in health care"
synonyms: specialist, authority, pundit, guru, oracle; adept, maestro, virtuoso, master, past master, professional, genius, wizard; connoisseur, aficionado, one of the cognoscenti, cognoscente, doyen, savant
If you want something less formal:
Go-to — M-W
always helpful : producing desired results or information when needed
relied on for expert knowledge or skill
"the company's go-to guy"
"He's the go-to guy in the office for tax information"
Even more informal, especially if it's the IT field:
Ninja — ODO
1.1 [OFTEN WITH MODIFIER] informal A person who excels in a particular skill or activity:
"My goal as marketing ninja is to get Thomas to spend less time in London, and more time on a plane, visiting his other ports of call."
"the courses vary—you don’t have to be a computer ninja to apply"
You can try and use panjandrum
