Say What?
Your teachers (or yogis) will mention a handful of terms that are unusual. You can bone up at Gidion's Yoga 101 . Start with this primer:

Asana
Exercise posture.

Ashram
Typically secluded community setting where yoga & meditation are practiced.

Chakras
The body's seven spiritual energy centers.

Dhyana
Meditation.

Guru
Yoga master/energy teacher.

Hatha
Yogic system of balancing the body's energies. Consists of physical exercises, known as asana.

Kapalabhati
Cleansing breath.

Kundalini
The body's energy that is found coiled at the base of the spine. Kundalini yoga uses breath, sound, and meditation as its major resources, specifically, moving the breath along the spine to stimulate different energy centers.

Mantra
Meditative sound and prayers.

Namaste
Sanskrit word meaning "I salute the spirit in you." Traditional Indian and Nepalese greeting.

Vinyasa
The flowing, preparatory steps taken to reach a specific goal of asana practice.