When you celebrate being with your significant other every month. But before completing a year together, it would just be a monthiversary.
When you celebrate your 1st Anniversary on the 15th of June, July 15th would be your 13th Anni-Monthiversary because it's 12 months + 1 month.
The Urban Dictionary Mug
One side has the word, one side has the definition. Microwave and dishwasher safe. Lotsa space for your liquids.
Buy the mug