linear unit vs em

Other hyponyms of linear unit include long measure, astronomy unit, metric linear unit, nautical linear unit, in, inch, foot, ft, footer, pace, yard, yarder, perch, pole, rod, furlong, international mile, land mile, mi, mile, stat mi, statute mile, miler, 880 yards, half mile, 440 yards, quarter mile, league, ligne, nail, archine, coss, kos, vara, verst, cable's length, cable, cable length, chain, cubit, digit, finger's breadth, finger, fingerbreadth, fistmele, body length, handbreadth, handsbreadth, head, lea, li, link, mesh, mil, mil, mile, Swedish mile, mile, Roman mile, Roman pace, geometric pace, military pace, palm, span, survey mile, fathom, fthm, point, pica, pica em, en, nut, cicero, daktylos, quarter of meridian, point size, catholic meter, catholic metre, metro cattolico, universal meter, universal metre.