thin thin /ˈθɪn/

adjective

1. () Of relatively small extent from one surface to the opposite or in cross section  ( thin )
   of relatively small extent from one surface to the opposite or in cross section
    Thin wire
   thin wire
    A thin chiffon blouse
   a thin chiffon blouse
    A thin book
   a thin book
    A thin layer of paint
   a thin layer of paint
   
2. () Lacking excess flesh  ( lean , thin )
   lacking excess flesh
    You can't be too rich or too thin
   you can't be too rich or too thin
    Yon Cassius has a lean and hungry look
   Yon Cassius has a lean and hungry look
   
3. () Very narrow  ( slimline , slender , thin )
   very narrow
    A thin line across the page
   a thin line across the page
   
4. () Not dense  ( thin , sparse )
   not dense
    A thin beard
   a thin beard
    Trees were sparse
   trees were sparse
   
5. () Relatively thin in consistency or low in density; not viscous  ( thin )
   relatively thin in consistency or low in density; not viscous
    Air is thin at high altitudes
   air is thin at high altitudes
    A thin soup
   a thin soup
    Skimmed milk is much thinner than whole milk
   skimmed milk is much thinner than whole milk
    Thin oil
   thin oil
   
6. (of sound) lacking resonance or volume  ( thin )
   (of sound) lacking resonance or volume
    A thin feeble cry
   a thin feeble cry
   
7. Lacking substance or significance  ( flimsy , fragile , slight , tenuous , thin )
   lacking substance or significance
    Slight evidence
   slight evidence
    A tenuous argument
   a tenuous argument
    A thin plot
   a thin plot
    A fragile claim to fame
   a fragile claim to fame
   
8. Lacking spirit or sincere effort  ( thin )
   lacking spirit or sincere effort
    A thin smile
   a thin smile
   

adverb

1. Without viscosity  ( thin , thinly )
   without viscosity
    The blood was flowing thin
   the blood was flowing thin
   

verb

1. () Lose thickness; become thin or thinner  ( thin )
   lose thickness; become thin or thinner
   
2. Take off weight  ( reduce , slenderize , slim , melt off , slim down , thin , lose weight )
   take off weight
     The snow began to melt off under the warm sun.
   The snow began to melt off under the warm sun.
   
3. Lessen the strength or flavor of a solution or mixture  ( cut , reduce , thin , dilute , thin out )
   lessen the strength or flavor of a solution or mixture
    Cut bourbon
   cut bourbon
   
4. Make thin or thinner  ( thin )
   make thin or thinner
    Thin the solution
   Thin the solution