Here are some of the Japanese terms that you might hear in training.
General
dojo
nage
seiza
sensei
shomen
uke
ukemi
Equipment
bokken
gi
hakama
jo
tanto
Techniques
hiji tori
ikkyo
kaiten nage
kata tori
katate ryote mochi
katate tori
kokyu nage
kotegaeshi
mae keri
mawashi keri
nikkyo
ryote tori
sankyo
shiho nage
shomen uchi
tsuki
ushiro hiji tori
ushiro kata tori
ushiro kubishime
ushiro tekubi tori
yoko keri
yokomen uchi
yokomen uchi hantai
Training hall
1. The person throwing
2. A throwing technique
Formal seated posture
Teacher, title of respect
1. The area at the front of the dojo
2. Short for shomen uchi (see Techniques)
The person being thrown
Rolls and breakfalls
Wooden practice sword
Aikido uniform
Divided skirt worn by blackbelts
4 1/2 foot wooden staff
Knife (usually a wooden practice knife)
Grabbing an elbow
Pinning technique with arm out to the side
"Head over heels" throw
Grabbing the shoulder/lapel
Holding one hand with both hands
Grabbing one hand
Timing throw (literally "breath throw")
Throw accomplished by twisting the wrist
Front kick
Roundhouse kick
Wrist lock with the arm in a Z shape
Grabbing both hands
Wrist lock with hand turned under the armpit
Throw with the hand behind the shoulder
Downward strike to the front of the head
Punch or thrust
Grabbing both elbows from behind
Grabbing both shoulders from behind
Choking from behind
Grabbing both hands from behind
Side kick
Forehand strike to the side of the head
Backhand strike to the side of the head