And for a long period of time.


He spent several nights [...] the terrorist's building.

I checked the synonyms of watch (noun lookout), but found nothing that could fit. There's also track, but I think it implies walking:

follow the trail or movements of (someone or something), typically in order to find them or note their course.

Maybe to keep vigil?

  • 15
    Studying, perhaps? Commented May 13, 2015 at 11:27
  • @StoneyB Studying a building? I think it doesn't fit very well.
    – wyc
    Commented May 13, 2015 at 11:28
  • 5
    Monitoring, surveying, or your very own observing.
    – RegDwigнt
    Commented May 13, 2015 at 11:37
  • 4
    "Surveilling" is the word used in all the cop shows.
    – Hot Licks
    Commented May 13, 2015 at 11:55
  • 2
    @janoChen: You certainly can study a building. You can study the back of your hand, for that matter. Or anything else.
    – Robusto
    Commented May 13, 2015 at 12:03

16 Answers 16


If informal usage would work for you you could use:

stake out as a verb:

they’d staked out Culley’s flat for a day (ODO)

He spent several nights staking out the terrorist's building.


Surveilling: verb (transitive) 1. to observe closely the activities of (a person or group)



The act of checking out a location, particularly in the context of the military, is called reconnoitering. One can also make a reconnaisance of a place, like before attempting to occupy it. (M-W)

  • I am reminded that Garrison Keillor, in a rare slip of the tongue, used "reconnoiter" when he meant "rendezvous" in one of his Writers' Almanac segments.
    – Hot Licks
    Commented May 14, 2015 at 11:37
  • lol @HotLicks even professional writers could get confused, I guess.
    – Quillmondo
    Commented May 14, 2015 at 13:30

He spent several nights casing the terrorist's building.

Appropriate if the surveillance is done in anticipation of a crime, especially a robbery. Also applies specifically to places or locations, not people nor things therein. (For example, you case a bank, but not a bank manager nor a bank safe.)

From Merriam Webster:

to study or watch (a house, store, etc.) with plans to rob it

From Oxford Dictionaries:

informal Reconnoitre (a place) before carrying out a robbery

  • 1
    Using of law enforcement reconnoitering a criminal establishment is decent play on words, especially if building a broader ironic metaphor. +1
    – Patrick M
    Commented May 14, 2015 at 4:39

Most of the good words are taken.

One isn't:

studying [Oxford: verb, sense 2]

to watch or to look at somebody/something carefully in order to find out something

  • I'm not sure this quite works. "Studying" could just mean staring at the plans, whereas the question seems to involve looking at the actual building. Commented May 14, 2015 at 9:19
  • 1
    @DavidRicherby: If you stare at the plans, you're studying the plans. If you stare at the building, you're studying the building. Anyway, I thought of the answer based on the title.
    – Tushar Raj
    Commented May 14, 2015 at 9:21
  • But if you stare at the plans, you're also studying the building. My point is that "studying the building" includes the possibility of not going anywhere near it, just as "The historian studies King Louis XIV" doesn't mean "She goes and looks at some dead guy's corpse." Commented May 14, 2015 at 9:29
  • 1
    @DavidRicherby: Now you're being intentionally funny. There are two senses of study. The sense I think is applicable, I've quoted. Your latest example likely uses study in sense 1. There are lots of words with multiple senses and it's easy to split hairs arguing that it would mean something else if you see it my way.
    – Tushar Raj
    Commented May 14, 2015 at 9:32
  • No, I'm not being funny. If you say to somebody "I studied the building", they may misunderstand you; if you say "I reconnoitred/surveilled/staked out the building", they will not misunderstand you. Why would you want to use a word that could be misunderstood when there are plenty of words available that would not be misunderstood? The "study the plans" misinterpretation is very plausible: we've all seen movies where the good/bad guys study the plans of a building before assaulting it. Commented May 14, 2015 at 9:48

He spent several nights surveying the terrorist's building? Perhaps 'analyzing'?

http://www.thesaurus.com/browse/study might help inspire you!

  • "Surveying" implies being there with a surveyor's transit and stick.
    – Hot Licks
    Commented May 13, 2015 at 11:56
  • 2
    Not really: verb (used with object) 1. to take a general or comprehensive view of or appraise, as a situation, area of study, etc. 2. to view in detail, especially to inspect, examine, or appraise formally or officially in order to ascertain condition, value, etc.
    – Herr Pink
    Commented May 13, 2015 at 11:57
  • I'm just saying what the reader will read.
    – Hot Licks
    Commented May 13, 2015 at 11:59
  • @HotLicks I agree that it sounds like the job of surveying in this context because of building, but I think the appraisal definition is more widely used and known.
    – Adam
    Commented May 13, 2015 at 18:40

To scrutinize may be another option:

  • to examine or observe with great care; inspect critically.

  • to examine carefully or in minute detail.

The Free Dictionary

  • 'Scrutinize' to some extent implies close proximity to me, though.
    – hBy2Py
    Commented May 13, 2015 at 19:42

To "monitor" is to continuously observe a defined subject

To "monitor" has for me the strongest implication of continuous attention regarding new knowledge to gain.
In the example, it is about collecting all relevant information, not to work with the infromation instead, which would draw attention from collecting.

So studying it, and investigating - all that comes later, based on the result of monitoring.


How about Spying

One who secretly collects information concerning the enemies of a government or group

Apart from the information collection being done secretly, I believe this word would fit in your requirement.

  • Spying has rather negative connotations but it does accurately describe the situation. Commented May 14, 2015 at 9:20

Scouting was what came to mind immediately for me.

He spent several nights scouting the terrorist's building.


Sizing up sounds best to me although slightly colloquial:

He spent several nights sizing up the terrorist's building.

or more formally evaluating at the risk of losing some of the flavour:

He spent several nights evaluating the terrorist's building.



verb \ˈgräk\

grokked grok·king

Definition of GROK:

transitive verb: to understand profoundly and intuitively

Examples of GROK

the eternal struggle of the human race to grok its place in the grand scheme of the universe

  • Welcome to the ELU :-)! This is a great word, although I'm not sure that the OP had intuition in mind. Your answer would be even better if you referenced the dictionary the definition is from (you can edit your post to do that) , but for a first answer it is quite a nice one :-).
    – Lucky
    Commented May 13, 2015 at 23:45
  • 1
    This doesn't work. To "grok" is to understand but the question asks for a verb that means to acquire information. You could say that, after staking out the building, he grokked the terrorists' behaviour but that's one stage beyond what's being asked for. Commented May 14, 2015 at 9:23

Combing through is an expression that fits your example well.

  • "Comb the desert!"
    – Zachiel
    Commented May 13, 2015 at 15:40
  • No. To comb through something is to search it carefully. This doesn't apply to the situation described in the question. Commented May 14, 2015 at 9:21

Auditing, like auditing a college course

  • Welcome to ELU, Mark! I'd say this is a pretty close word for it, but Oxford says audit is more of a review and not an intake of something. Also, be sure to elaborate on your answer to help everyone out.
    – Adam
    Commented May 13, 2015 at 18:32
  • Welcome to ELU, Mark. There are several things you could do to improve your answer.
    – ScotM
    Commented May 14, 2015 at 0:39

"peruse" - IMHO the best word possible to mean, “observing something with the purpose of gaining knowledge from it”. Although "examine" is pretty near exactly the same.

  • "Peruse" has a strong connotation, if not denotation, of superficially examining something for the purpose of amusement. Commented May 13, 2015 at 19:35
  • @KevinKrumwiede Superficially? ODO disagrees:"peruse: Examine carefully or at length:" How well it fits (or does not fit) the OP's needs might be a subject for discussion, but it is a legitimate answer. Milo, welcome to the ELU :-). You could prevent disagreement with your answer if you edit your post to include references.
    – Lucky
    Commented May 13, 2015 at 19:57

The most reliable knowledge is that acquired by the scientific method.

Four essential elements of the scientific method are iterations, recursions, inter-leavings, or orderings of the following:

  • Characterizations (observations, definitions, and measurements of the subject of inquiry)
  • Hypotheses (theoretical, hypothetical explanations of observations and measurements of the subject)
  • Predictions (reasoning including logical deduction from the hypothesis or theory)
  • Experiments (tests of all of the above)
    Wikipedia: Elements of the Scientific Method

So to gain knowledge scientists need to characterize the subject of inquiry. One possible term for this process might be "data collection" but you'll be hard pressed to find a better term than your own, as @RegDwigнt already commented


transitive verb

  • 1.a. To be or become aware of, especially through careful and directed attention; notice: observed a car leaving the property.
  • 1.b. To watch attentively: observe a child's behavior.
  • 1.c. To make a systematic or scientific observation of: observe the orbit of a comet.

A great example of making observations over a long period of time was

Tycho Brahe, born Tyge Ottesen Brahe (14 December 1546 – 24 October 1601), was a Danish nobleman known for his accurate and comprehensive astronomical and planetary observations. He was born in Scania, then part of Denmark, now part of modern-day Sweden. Tycho was well known in his lifetime as an astronomer, astrologer and alchemist, and has been described more recently as "the first competent mind in modern astronomy to feel ardently the passion for exact empirical facts."

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