Peel the onions and slice them ¼ “ thick; separate the slices into rings. Divide the onion rings amoung 3 clean, dry pint canning jars.
To the onions in each jar add 6 whole cloves, 6 peppercorns, 1 teaspoons mustard seed and ½ teaspoons celery seed.
Combine the vinegar, water, sugar, salt, turmeric and cinnamon in a stainless-steel or other non-reactive saucepan. Heat to boiling, then simmer 2 minutes.
Fill the jars with the hot liquid, leaving ¼ “ of headspace. Remove any air bubbles by running a long thin knife blade or a cooking chopstick around the inside walls of the jars and add liquid if necessary to maintain the ¼ “ of headspace.
For refrigerator storage - let the jars cool uncovered, then cover with a doubled sheet of plastic wrap and a cap, any kind, that fits the jar. Refrigerate for at least 2 weeks before serving. The pickles keep (and improve) for many months in the fridge.