tra·che·ar·y element 
(trākē-ĕr′ē)
(trākē-ĕr′ē)n.
Either of two types of elongated water-conducting cells having lignified walls and found in the xylem of vascular plants; a tracheid or vessel element.
[Obsolete trachea, a water-conducting structure in xylem resembling insect tracheae; see TRACHEA + -ARY.]