open open /ˈoʊpən/

adjective

1. () Affording unobstructed entrance and exit; not shut or closed  ( unfastened , open )
   affording unobstructed entrance and exit; not shut or closed
    An open door
   an open door
    They left the door open
   they left the door open
   
2. () Affording free passage or access  ( open )
   affording free passage or access
    Open drains
   open drains
    The road is open to traffic
   the road is open to traffic
    Open ranks
   open ranks
   
3. () With no protection or shield  ( exposed , open )
   with no protection or shield
    The exposed northeast frontier
   the exposed northeast frontier
    Open to the weather
   open to the weather
    An open wound
   an open wound
   
4. () Open to or in view of all  ( open )
   open to or in view of all
    An open protest
   an open protest
    An open letter to the editor
   an open letter to the editor
   
5. () Not having been filled  ( open )
   not having been filled
    The job is still open
   the job is still open
   
6. () Used of mouth or eyes  ( opened , open )
   used of mouth or eyes
    Keep your eyes open
   keep your eyes open
    His mouth slightly opened
   his mouth slightly opened
   
7. () Accessible to all  ( open )
   accessible to all
    Open season
   open season
    An open economy
   an open economy
   
8. () Having no protecting cover or enclosure  ( open )
   having no protecting cover or enclosure
    An open boat
   an open boat
    An open fire
   an open fire
    Open sports cars
   open sports cars
   
9. () (of textures) full of small openings or gaps  ( loose , open )
   (of textures) full of small openings or gaps
    An open texture
   an open texture
    A loose weave
   a loose weave
   
10. () Not defended or capable of being defended  ( assailable , undefendable , undefended , open )
    not defended or capable of being defended
     An open city
    an open city
     Open to attack
    open to attack
    
11. () Without undue constriction as from e.g. tenseness or inhibition  ( open )
    without undue constriction as from e.g. tenseness or inhibition
     The clarity and resonance of an open tone
    the clarity and resonance of an open tone
     Her natural and open response
    her natural and open response
    
12. () (set theory) of an interval that contains neither of its endpoints  ( open )
    (set theory) of an interval that contains neither of its endpoints
    
13. () Not sealed or having been unsealed  ( opened , open )
    not sealed or having been unsealed
     The letter was already open
    the letter was already open
     The opened package lay on the table
    the opened package lay on the table
    
14. () Not brought to a conclusion; subject to further thought  ( undecided , undetermined , unresolved , open )
    not brought to a conclusion; subject to further thought
     An open question
    an open question
     Our position on this bill is still undecided
    our position on this bill is still undecided
     Our lawsuit is still undetermined
    our lawsuit is still undetermined
    
15. Ready for business  ( open )
    ready for business
     The stores are open
    the stores are open
    
16. Openly straightforward and direct without reserve or secretiveness  ( candid , heart-to-heart , open )
    openly straightforward and direct without reserve or secretiveness
     His candid eyes
    his candid eyes
     An open and trusting nature
    an open and trusting nature
     A heart-to-heart talk
    a heart-to-heart talk
    
17. Affording free passage or view  ( open , clear )
    affording free passage or view
     A clear view
    a clear view
     A clear path to victory
    a clear path to victory
     Open waters
    open waters
     The open countryside
    the open countryside
    
18. Open and observable; not secret or hidden  ( open , overt )
    open and observable; not secret or hidden
     An overt lie
    an overt lie
     Overt hostility
    overt hostility
     Overt intelligence gathering
    overt intelligence gathering
     Open ballots
    open ballots
    
19. Ready or willing to receive favorably  ( open , receptive )
    ready or willing to receive favorably
     Receptive to the proposals
    receptive to the proposals
    
20. Possibly accepting or permitting  ( open , subject , capable )
    possibly accepting or permitting
     A passage capable of misinterpretation
    a passage capable of misinterpretation
     Open to interpretation
    open to interpretation
     An issue open to question
    an issue open to question
     The time is fixed by the director and players and therefore subject to much variation
    the time is fixed by the director and players and therefore subject to much variation
    
21. Not requiring union membership  ( open )
    not requiring union membership
     An open shop employs nonunion workers
    an open shop employs nonunion workers
    

noun

1. () Where the air is unconfined  ( open air , outdoors , open , out-of-doors )
   where the air is unconfined
    He wanted to get outdoors a little
   he wanted to get outdoors a little
    The concert was held in the open air
   the concert was held in the open air
    Camping in the open
   camping in the open
   
   
2. () A clear or unobstructed space or expanse of land or water  ( clear , open )
   a clear or unobstructed space or expanse of land or water
    Finally broke out of the forest into the open
   finally broke out of the forest into the open
   
3. Information that has become public  ( open , surface )
   information that has become public
    All the reports were out in the open
   all the reports were out in the open
    The facts had been brought to the surface
   the facts had been brought to the surface
   
4. A tournament in which both professionals and amateurs may play  ( open )
   a tournament in which both professionals and amateurs may play
   

verb

1. () Cause to open or to become open  ( open up , open )
   cause to open or to become open
    Mary opened the car door
   Mary opened the car door
   
2. () Start to operate or function or cause to start operating or functioning  ( open up , open )
   start to operate or function or cause to start operating or functioning
    Open a business
   open a business
   
3. () Become open  ( open up , open )
   become open
    The door opened
   The door opened
   
4. () Begin or set in action, of meetings, speeches, recitals, etc.  ( open )
   begin or set in action, of meetings, speeches, recitals, etc.
    He opened the meeting with a long speech
   He opened the meeting with a long speech
   
5. () Make available  ( open up , open )
   make available
    This opens up new possibilities
   This opens up new possibilities
   
6. () Spread out or open from a closed or folded state  ( spread out , unfold , open , spread )
   spread out or open from a closed or folded state
    Open the map
   open the map
    Spread your arms
   spread your arms
   
7. () Become available  ( open , open up )
   become available
    An opportunity opened up
   an opportunity opened up
   
8. () (chess) make the opening move  ( open )
   (chess) make the opening move
    Kasparov opened with a standard opening
   Kasparov opened with a standard opening
   
9. () Have an opening, passage or outlet  ( open )
   have an opening, passage or outlet
    The bedrooms open into the hall
   The bedrooms open into the hall
   
10. Display the contents of a file or start an application as on a computer  ( open )
    display the contents of a file or start an application as on a computer
    
11. Afford access to  ( afford , give , open )
    afford access to
     The door opens to the patio
    the door opens to the patio
     The French doors give onto a terrace
    The French doors give onto a terrace