first slip system to become active because of the critical resolved shear stress on the system is attained earlier than on the others (see: primary slip; compare: secondary slip system), esmasene aktiivne libisemissüsteem kristallis, mis on nihkepingest tulenevalt otsustav teiste ees (vt esmalibisemine kristallis; vrd sekundaarlibisemissüsteem kristallis)