Omote‑waza: Technique which goes  forward or to uke’s front.

Ura‑waza: Technique which goes around or behind uke.

Irimi: Entering.

Tenkan: Turning, a subset of ura‑waza.

NOTE: The whole name of a technique in Japanese is formed by the word for the attack, then the technique, then the direction or variation.

For example:

 Attack                                 Technique                     Direction

shomen‑uchi                              ikkyo                           omote

katate‑dori                                shiho‑nage                    ura