late 14c., "having no apparent motion" (in reference to planets), from Middle French stationnaire "motionless" and directly from Latin stationarius, from the stem of statio "a standing, post, job, position" (see station (n.)). Meaning "unmovable" is from 1620s. In classical Latin, stationarius is recorded only in the sense "of a military station;" the word for "stationary, steady" being statarius.