periodiccia 

A Periodic Table of Elements Discord Bot - Very epic!

Periodiccia helped me ace my chemistry exam - I recommend it!

periodiccia by QuackerDeezles March 19, 2021

Periodicity 

The pains, cramps, and aches associated with a woman's menstrual cycle.

She laid on the couch, complaining about her periodicity.

Sometimes periodicity is so bad, one might not go into school or work that day.

Periodicity by Theotherdudeyouknow December 13, 2012

periodisiac 

A person who is obcessed with using periods in Instant Messages. Typically uses improper grammar with the only punctuation being periods. In some cases, the periods come between words, as a comma would.

Periodisiac Example 1: "dang. that was awesome. wow."

Periodisiac Example 2: "lol..haha..awesome.."

periodisiac by MCV August 18, 2006