psychrometer psychrometer /saɪˈkrɔmɪtər/

noun

1. A hygrometer consisting of a dry-bulb thermometer and a wet-bulb thermometer; their difference indicates the dryness of the surrounding air  ( psychrometer )
   a hygrometer consisting of a dry-bulb thermometer and a wet-bulb thermometer; their difference indicates the dryness of the surrounding air
    The meteorologist used a psychrometer to gauge the humidity in the atmosphere.
   The meteorologist used a psychrometer to gauge the humidity in the atmosphere.
   
   

 gear gear /ˈgɪr/

noun

1. () A toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion  ( cogwheel , gear wheel , geared wheel , gear )
   a toothed wheel that engages another toothed mechanism in order to change the speed or direction of transmitted motion
   
   
2. Equipment consisting of miscellaneous articles needed for a particular operation or sport etc.  ( appurtenance , gear , paraphernalia )
   equipment consisting of miscellaneous articles needed for a particular operation or sport etc.
   
   
3. A mechanism for transmitting motion for some specific purpose (as the steering gear of a vehicle)  ( gear , gear mechanism )
   a mechanism for transmitting motion for some specific purpose (as the steering gear of a vehicle)
   
   
4. Wheelwork consisting of a connected set of rotating gears by which force is transmitted, motion or torque is changed  ( gear , gearing , geartrain , power train , train , drivetrain )
   wheelwork consisting of a connected set of rotating gears by which force is transmitted, motion or torque is changed
    The fool got his tie caught in the geartrain
   the fool got his tie caught in the geartrain
   
   

verb

1. () Set the level or character of  ( pitch , gear )
   set the level or character of
    She pitched her speech to the teenagers in the audience
   She pitched her speech to the teenagers in the audience
   

 50 50 /ˈfɪfti/

adjective

1. () Being ten more than forty  ( l , fifty , 50 )
   being ten more than forty
     She purchased fifty balloons for the birthday party.
   She purchased fifty balloons for the birthday party.
   

noun

1. () The cardinal number that is the product of ten and five  ( L , fifty , 50 )
   the cardinal number that is the product of ten and five
    The speed limit on this road is fifty miles per hour
   The speed limit on this road is fifty miles per hour
   
   

 chlorine chlorine /ˈklɔriːn/

noun

1. () A common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)  ( atomic number 17 , Cl , chlorine )
   a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)
     Chlorine is commonly used to disinfect swimming pools.
   Chlorine is commonly used to disinfect swimming pools.