I'm looking for a word,phrase, idiom to describe a person who doesn't want to share their knowledge to other colleagues and doesn't want to teach others the way of doing something because he is afraid of losing his position in the company or being left behind by his colleagues.

I think of this word: "protective over something". For example in this sentence: My manager is quite protective over his work; he doesn't want to teach me anything.
However, I'm not sure whether the word "protective over" is correct or not. Could you help me out?

Thank you so much.

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  • I'm really sorry for any mistake that I've made. I'm a English learner, so sometimes i couldn't use correct grammar or use suitable writing style. I have just edited my post. Could you review once again? Thank you admins
    – Huong
    Commented Jun 21, 2018 at 9:20

11 Answers 11


They keep their information close to their chest:

hold/keep/play (something) close to one's chest
variants: or US hold/keep/play (something) close to the vest

to keep (something) to oneself · It's better to hold such information close to the vest. · She tends to keep her opinions close to her chest.

  • 1
    nice ... but does not imply the motive mentioned by OP.
    – lbf
    Commented Jun 20, 2018 at 12:20

Although I don't have a dictionary reference, it's common to see this behaviour called Knowledge Hoarding:

Knowledge hoarder (noun): a person who gathers and guards information for personal preservation and future use.

Knowledge sharer (noun): a person who actively, purposely and happily gives information to others.

(from Knowledge Hoarders vs. Knowledge Sharers by Alison Cooley)

Other relevant articles:

  • Based on the words themselves, "knowledge hoarder" doesn't say anything about the person's willingness to share the information. As an example, just because someone hoards newspapers doesn't mean they want to ensure that others don't have a newspaper.
    – Flater
    Commented Jun 20, 2018 at 13:55
  • True, but the majority of uses I found with a Web search seem to carry that connotation. Hoarding of physical things deprives others of their use, so perhaps some of that carries over to the abstract domain? Commented Jun 20, 2018 at 14:02
  • One can hoard phhsical items without depriving others as well, as per the newspaper example.
    – Flater
    Commented Jun 20, 2018 at 14:05
  • You're right; I'm keeping this suggestion here, though, as the first link (Alison Cooley) definitely sets up hoarders as the antithesis of sharers. Perhaps you could suggest a more unambiguous alternative? Commented Jun 20, 2018 at 14:08

If such word exists, it eludes me — but I'm thinking of secretive, unforthcoming. Such person is said to withhold information.


If I was being slightly sardonic (and in a computing related field), I'd describe such a person as a data sink

Definition (from McGraw-Hill):

data sink (computer science) A memory or recording device capable of accepting data signals from a data transmission device and storing data for future use.

That is, your manager absorbs all the information around him but never retransmits it to you. It is more a technical term rather than a description of a person, but sometimes an analogy is the fastest method of communication, especially if you are dealing with computer scientists. It also describes what he is doing without any implications as to why he is doing it.

And if you want to argue your case with him, you could say it is best for you to learn a lot about his job so that he is then free to be promoted. He shouldn't be stuck in a position he is overqualified for simply because he hasn't communicated the correct skills to his team.

Your suggestion of "protective" is clear and respectful. I'd say it's both correct and as polite as you can be.


Uninclined to offer.. Uncooperative/ Unobliging.


You could call such a person a monopolizer, where the verb monopolize means:

To dominate or to get total control of something by excluding everyone else


Hmmm? Selfish?

Cambridge Dictionary

selfish definition: Someone who is selfish only thinks of their own advantage.

  • add a reference for your definition of selfish and answer will be better recieved.
    – lbf
    Commented Jun 20, 2018 at 12:21
  • Avoiding being fired isn't really a matter of selfishness. I'd be more inclined to call it a misguided sense of selfpreservation.
    – Flater
    Commented Jun 20, 2018 at 13:53

They protect their

fiefdom (TFD)

An organization or department over which one dominant person or group exercises control.


turf (TFD)

The range of the authority or influence of a person, group, or thing



To sandbag is to lower expectations of a company's or individual's strength in order to produce greater than anticipated results. Sandbagging, in business, is most often seen when company managers temper the expectations of shareholders by giving guidance below what they know will be achieved. (Investopedia)


To deliberately perform at a lower level than you are capable of (Urban Dictionary)


When a player in any game chooses (on purpose) to not play their best. Normally this is because they are too superior, they want to hustle you, or they are too lazy to play their best with nothing on the line. (Urban Dictionary)


Poker: to deceive (one or more opponents) into remaining in the pot by refraining from betting on a strong hand, then raising the bet in a later round. Informal: to gain an advantage over (one or more competitors) by concealing one's abilities or other strengths early in a game or other competitive activity. Informal: to gain an advantage by concealing or downplaying the strengths of (something). (Dictionary.com)



"not candid or sincere, typically by pretending that one knows less about something than one really does."


  • Add a reference for your definition and answer will be better received.
    – lbf
    Commented Jun 20, 2018 at 12:22
  • 1
    Your answer fits with the title, but not really the question body. It's not a matter of hiding that they have skills; it's quite the opposite: ensuring that others are aware that only they have the needed skill/knowledge.
    – Flater
    Commented Jun 20, 2018 at 13:56

conceal (someone or something) from (someone or something) idiom

To hide someone or something from someone or something.

As in:

Our manager conceals his job talents from fellow workers lest it be used to our advantage too.

At first blush Hide one’s light under a bushel is an idiom some have misused, as the 'light' is concealed because of vanity, not jealously.

  • Surely "hiding one's light" is usually through modesty, rather than vanity? Unless there's a context where being more knowledgeable is perceived as lower status. (Obviously the fact that I'm here on SE means I find it hard to imagine such a context). Commented Jun 20, 2018 at 14:05
  • @TobySpeight as the 2nd idiom was not my answer I take the fifth! Haid i used the ' light' idiom i would have spent more time on IT. so humility!
    – lbf
    Commented Jun 20, 2018 at 14:28

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