Dishwasher

A dishwasher comprising:

• a tub that defines a washing space;
• a sump disposed below the tub and configured to store wash water therein;
• a pump configured to supply the wash water stored in the sump to the tub;
• and
• a spray arm configured to supply the wash water from the pump to the washing space,
• wherein the spray arm comprises:
• a bubble generator configured to generate microbubbles in the wash water and to supply the wash water including the microbubbles to the washing space, the
• bubble generator defining a bubble generation flow path configured to generate the microbubbles, and
• a hub configured to supply the wash water discharged from the pump to the bubble generator,
• wherein the bubble generation flow path comprises:
• a first expansion passage that extends from an inlet end of the bubble generator and defines a first increased flow path cross-sectional area,
• a reduction passage that extends from the first expansion passage and defines a decreased flow path cross-sectional area, and
• a second expansion passage that extends from the reduction passage and defines a second increased flow path cross-sectional area, and
• wherein the bubble generator has an inlet hole that is defined between the reduction passage and the second expansion passage and configured to introduce air
• into the bubble generator flow path.