It's a question that was asked in an aptitude test I appeared in. It seems pretty straightforward but I gave the answer "Lighting". The released answer says "Lightening" which looks right logically from the look of it but is it? I tried to research a bit but couldn't find much. I read somewhere that "to light" can mean "whiten" so lighting should mean whitening if the first one is taken as true. Light has many meanings so if it's seen as just the adding of "-ening" as a procedure and not going into meaning, it is right to take "lightening" as answer in my opinion too. Would love to hear from those interested in this little question.


2 Answers 2


They're tricking you on the test by employing the old causative/inchoative suffix -en. It used to be very common in English, but it only appears on a few words in Modern English.

Many of them are colors:

  • white ~ whiten 'make or become white(r)'
  • red ~ redden 'make or become red(der)'
  • dark ~ darken 'make or become dark(er)'
  • black ~ blacken 'make or become black(er)'
  • light ~ lighten 'make or become light(er)'

but not all colors. The following do not exist and sound terrible:

  • *bluen, *orangen, *greenen, *purplen

Light also has the meaning 'not heavy', and lighten the load dutifully means to make the load lighter in that sense, even though it has nothing to do with colors.

Another oddity of -en is that the suffix can be used as a prefix, with the right words:

  • joy ~ enjoy
  • rage ~ enrage

and occasionally as both together:

  • light ~ lighten ~ enlighten

which is yet another oddity. English is full of them.

  • 1
    This answer embiggens a small question. Feb 21, 2020 at 16:51
  • 1
    The en- in enjoy/enrage is not the same as the causative/inchoative suffix -en; it’s rather the same as in-. May 29, 2020 at 14:54

Merriam Webster has these definitions for "to light":

intransitive verb
1 : to become light : brighten —usually used with up
    her face lit up
2 : to take fire
3 : to ignite something (such as a cigarette) —often used with up
transitive verb
1 : to set fire to
2a : to conduct with a light : guide
    b : illuminate 
        rockets light up the sky
    c : animate, brighten 
        a smile lit up her face

Notice that used without "up" as in "to light up", it usually doesn't mean to brighten, and even then it's more about becoming bright (with light) rather than becoming closer to the color white.

You may instead be thinking of to lighten: to make (something, such as a color) lighter, which becomes "lightening". Compare with to whiten: make something white or whiter (to white is an archaic form of to whiten)

  • Anything you can say about 'lightening' (the central point of the question)?
    – Mitch
    Feb 20, 2020 at 17:08
  • @Mitch Not sure what more I can say besides what I did in the last paragraph: it's a form of "to lighten", not of "to light". Was there anything in particular you found unclear or missing?
    – S.T. Veje
    Feb 21, 2020 at 6:01
  • Did you find 'lightening' in a dictionary? What did it say?
    – Mitch
    Feb 21, 2020 at 12:05
  • @Mitch Check the second link in my answer. Above "Definition of lighten".
    – S.T. Veje
    Feb 22, 2020 at 9:24
  • Then why didn't you copy that part first and explain that rather than the M-W definition you gave which doesn't mention it at all.
    – Mitch
    Feb 22, 2020 at 16:18

Not the answer you're looking for? Browse other questions tagged or ask your own question.