spy

spy on (someone or something)

To observe someone or something in a clandestine or furtive manner, so as not to be noticed doing so. I can't believe you hired a private detective to spy on me—do you really distrust me that much? I was sent to spy on the foreign ambassador during his time in Washington.
See also: on, spy

spy out

1. To observe or investigate something or some place very closely or carefully in order to discover something or glean some information. A noun or pronoun can be used between "spy" and "out." We sent our best agents to spy the enemy encampment out in order to find a weak spot. I've been spying out some land to the west of town that could be suitable for our farm.
2. To discover something or glean some information as a result of close, careful observation. A noun or pronoun can be used between "spy" and "out." I've been sent to spy out what goes on behind closed doors at this factory. We so far haven't been able to spy any motive out for the attack.
See also: out, spy

spy out the land

To find out about or come to understand a particular state of affairs or the way a situation exists or has developed, especially before taking any decisive or definitive action. Given the turbulent nature of this market, I think it would be prudent for us to spy out the land before we agree to invest in your company. I'm just spying out the land regarding my parents' divorce before I make any solid plans to come visit them this Christmas.
See also: land, out, spy
Farlex Dictionary of Idioms.

spy (up)on someone or something

to watch someone or something to learn secret or concealed information. (Upon is formal and less commonly used than on.) Are you spying upon me? I wasn't spying on you! I was just trying to see who you were.
See also: on, spy
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

spy on

Secretly or furtively observe someone or something, as in The children loved spying on the grownups, or The company sent him to spy on the competitor's sales force. [Early 1600s]
See also: on, spy
The American Heritage® Dictionary of Idioms by Christine Ammer.

ˌspy out the ˈland

find out about a situation, a place, an organization, etc. before you make a decision: The manager is sending Mark to Iceland to spy out the land. He wants to know whether we can do business there.
See also: land, out, spy
Farlex Partner Idioms Dictionary

spy on

or spy upon
v.
To observe someone or something secretly and closely: A detective had been spying on the mayor's every move for months. The children spied upon their neighbors from the bushes along the property line.
See also: on, spy

spy out

v.
1. To observe some place secretly and closely: The troops spied out the cave and decided it was safe to hide there. The explorers sent a scout into the valley to spy it out before descending.
2. To discover something by observing secretly and closely: Try to spy out what's going on on those rooftops. We followed the other teams' strategies carefully to spy them out.
See also: out, spy
The American Heritage® Dictionary of Phrasal Verbs.
See also:
  • spied
  • spies
  • spy on
  • spy on (someone or something)
  • sneak up
  • sneak up (on someone or something)
  • sneak up on
  • slip up on
  • slip up on (someone or something)
  • steal up on (someone or something)
References in periodicals archive
Ushered into the innermost sanctum of the spy world, the scientists got to push the buttons that control the ultrasecret satellites run by the National Reconnaissance Office (NRO), whose very name was classified until last year.
Spying on the environment
Durrani's summoning to the GHQ came after former premier Nawaz Sharif and Pakistan People's Party (PPP) Senator Raza Rabbani voiced their reservations over the book, which has been co-authored by former chief of India's spy agency Research and Analysis Wing (RAW) AS Dulat and Lt Gen (retd) Asad Durrani.
Spy Chronicles- Gen Durrani's name placed on ECL
Dulat and Lt Gen (retd) Asad Durrani's Spy Chronicles: RAW, ISI and the Illusion of Peace has been making headlines this week even before it hits shelves.
Politician would've been termed 'traitor' for teaming up with Indian counterpart to pen book: Rabbani
Go and act as a spy. Go and explore (spy) what they are doing and how they are doing it.
How to deliver a fortunate future
Yadav was working for Indian spy agency Research and Analysis Wing (RAW) and was facilitating banned groups in to spread violence in the province and the country, officials said.
Another network of Indian spies unearthed in Pakistan
Ultimate Spy holds all the information of a history textbook but reads like a collection of magazine articles, pulling readers into the time period by providing scoops on some of the most influential people in history.
Melton, H. Keith. Ultimate Spy: Inside the Secret World of Espionage
I spy with my little eye something beginning with N.
SPY
M2 PHARMA-December 9, 2014-Novadaq Technologies wins additional SPY fluorescence technology patent protection in the US
Novadaq Technologies wins additional SPY fluorescence technology patent protection in the US
M2 EQUITYBITES-December 9, 2014-Novadaq Technologies wins additional SPY fluorescence technology patent protection in the US
Novadaq Technologies wins additional SPY fluorescence technology patent protection in the US
Under a 2010 certification approved by the Foreign Intelligence Surveillance Court (FISA), NSA was permitted to spy on 193 foreign governments as well as foreign factions, political organisations and other entities, Washington Post had reported.
Pakistan formally lodges protest with US over spying issue
The 13 and 14-year-olds at Pendle Vale College, Nelson, Lancs, had been studying Stormbreaker, the first of Anthony Horowitz's novels featuring teen spy Alex Rider.
THE SPY MASTER; MI5 chief writes personal reply to school after pupils ask about life as spook for a class project; EXCLUSIVE
THE world of espionage will be centre stage at a spy festival organised by a university in the capital.
The spies have it at university's week-long espionage festival
AS THE Sunday ECHO celebrates its 007 edition, we take a look at some of the spy gadgets you can buy.
ON YOUR MERSEY'S SECRET SERVICE; We take a sneaky peek at gadgets on sale in city's answer to Q's workshop
Notable spy cases are spotlighted, including famous spies for the Soviets such as John Walker and Edward Lee Howard; the spy for China, Larry Wu-tai Chin; the spy for Israel, Jonathan Pollard; and many more.
American Spies
LEGACY (BBC Two, Thursday, 9pm) SHERLOCK villain Andrew "Moriarty" Scott is heading back to the 1970s for Cold War spy drama Legacy to play a Russian diplomat.
A lasting Legacy of Cold War; 7 TV treats of the week