Ear­li­er this week, one of my chil­dren asked me why eleven and twelve aren’t “one­teen” and “twoteen”, so I thought that would make an inter­est­ing blog top­ic today.

Both words have been around for cen­turies. Eleven was orig­i­nal­ly spelled as elleovene and came from an Old Eng­lish word—endle­o­fan—that appeared around the start of the 13th cen­tu­ry. Ulti­mate­ly derived from the Pro­to-Ger­man­ic ainalif, it lit­er­al­ly meant “one left” (ainaz mean­ing “one” and lif mean­ing “left”) because in a base-10 sys­tem some­times it’s handy to have a num­ber that refers to what’s left over after 10.

The word “twelve” hasn’t changed much, orig­i­nal­ly writ­ten as twelf. It, too, came from a Pro­to-Ger­man­ic com­pound word that includ­ed lif: twalif (twa mean­ing “two” and lif, of course, mean­ing “left”). Like its pre­de­ces­sor, it meant “two left”.

This, of course, rais­es the ques­tion as to why the pat­tern switched as of thir­teen. Unfor­tu­nate­ly, we don’t seem to know. That’s the Eng­lish lan­guage for you. :)

About Kim Siever

I am a copy­writer and copy­ed­i­tor. I blog on writ­ing tips most­ly, but I some­times throw in my thoughts about run­ning a small busi­ness.

Fol­low me on Twit­ter at @hotpepper.

Free monthlywriting &social media tips!

Free monthlywriting &social media tips!

Sign up to receive monthly writing and social media tips.

Thanks for signing up for our monthly writing tips!

Pin It on Pinterest