v.
    - push, fold, or turn under or between two surfaces or into a confined space:
 he tucked his shirt into his trousers.
 ▸
(tuck someone in/up)
 settle someone in bed by pulling the edges of the bedclothes firmly under the mattress.
 - 
(tuck something away)
 put or keep something in a secure or concealed place.
 - make a flattened, stitched fold in (a garment or material), to improve the fit or for decoration.
 - 
(tuck in/into)
 informal eat food heartily.
 
n.
   - a flattened, stitched fold in a garment or material. 
▸
informal a surgical operation which involves removing a fold of flesh or fat:
 tummy tuck.
 - Brit. informal food eaten by children at school as a snack.
 - 
(also tuck position)
 (in diving, gymnastics, downhill skiing, etc.) a position with the knees bent and held close to the chest.
 
 
  Derivative
  
  Etymology
  OE tūcian ‘to punish, ill-treat’, of W. Gmc origin.