Yes, onion cells are typically turgid.
The reference material provided states: "These cells are what is called 'turgid' that is they are pretty full of water and hence there is enough pressure against the rigid cell wall for the cells to keep their brick-like shape." This means that onion cells, when in a normal, healthy state, are full of water, creating pressure against their cell walls. This internal pressure, known as turgor pressure, is what gives the cells their rigidity and helps maintain their structure. The reference also points out that the cytoplasm is red throughout the cell, with the non-red part existing between the cell membrane and cell wall when the cell is turgid.
