Here are short definitions of a few basic Zen Buddhist terms:

dharani Chanted Buddhist verse or sutra
han A wooden instrument sounded during kinhin
kane A gong sounded during the zazen service
Kannon The Bodhisattva of compassion. Also known as Kuan Yin.
kinhin Walking Zen meditation
mokugyo A wooden slit-drum used to set the tempo during the Heart Sutra recitation
mu-shin Literally "no mind"
roshi Venerable teacher; also Zen master
sensei Literally "first born." Common meaning: teacher.
Shikantaza A form of Zen meditation in which one sits just for the sake of sitting.
Soto Zen One of the two primary schools of Zen in Japan. Founded by Dogen Zenji.
sutra A Buddhist scripture
zazen Zen meditation; sitting meditation
zazenkai A part-day or full-day session of Zen meditation
zendo Room where Zen meditation is practiced