Refers to a fixture or piece of furniture with a basin for washing hands and face, often found in bathrooms or washrooms.
We installed a new washstand in the washroom.
Water is leaking from the faucet of the wash basin.
流し台 refers specifically to a kitchen sink, while 手洗い台 is for washing hands and face, typically in a bathroom or washroom.
Compound of 手洗い (tearai, 'hand washing') and 台 (dai, 'stand, platform').