armrest vs pillow

armrest

• Part of the seat of a chair that is designed to support the arm. 

pillow

• A soft cushion used to support the head in bed. 

• A pillow lava. 

• The socket of a pivot. 

• A block under the inner end of a bowsprit. 

• A kind of plain, coarse fustian. 

• A piece of metal or wood, forming a support to equalize pressure; a brass; a pillow block. 

• To rest as on a pillow.