"A Fortiori" Chof Vov Iyar 5771
Many people don't know what it means but most people in our community are familiar with the concept. It translates to Kal Vchomer; here is an example:
If places that are open a few hours a day for learning are open throughout the entire night of Shavuos for learning, Kal Vchomer (a fortiori in Latin/English), a place that is open 6:00 AM - 2:00 AM regularly will be open throughout the entire night of Shavous. The latter is referring to the Heichal Halimmud.