Using a thick grater, grate the cucumber into pieces then squeeze the grated cucumber in handfuls over the sink to remove excess moisture. Transfer the squeezed cucumber to a bowl.
Then grate the onion (but keep the juices this time) and add to the bowl.
Add the yogurt, herbs, lemon juice, garlic, and salt to the bowl, and mix well. Taste and add additional dill, lemon , and/or salt, if desired.
Serve chilled after an hour ( or keep in fridge for up to 4 days).
Perfect with naan, rice, dolmas, pita sandwiches, etc.