Monday, June 15, 2009

Usage tip: complimentary vs. complementary

For me, the easiest way to remember the difference between these two is to remember the definitions of compliment (something nice you say about someone) and complement (something that completes a set or group).

Something that is complimentary is either a) free or b) flattering. (Maybe another way to remember it is to think "I like things that are complImentary". Or maybe that's just really corny.)

Something that is complementary completes a set, matches a pair, or fills out a group. Angles, base pairs, and wines can be complementary, but statements and newspapers generally aren't.

So, you can sip complimentary coffee while contemplating the complementary angles on the rafters above your head. But if you start encountering complimentary angles, you might want to get your eyes (ears?) checked...

11 comments:

Nibornm said...

To simplify this task I recommend the following key:

ComplEmentary is something Extra

vs.

ComplImentary is the opposite of an Insult

Dave said...

well appreciated!

Anonymous said...

But the question remains: Can the glass of wine be both complimentary (on the house) and at the same time complementary (in that it matches well with the rest of the meal)?

terry said...

surely a complementary glass of wine is on the house.

Ian said...

No, as the previous poster said; a complimentary (i.e. free) glass of wine is on the house. You would hope the wine would be complementary (completes/matches well with) to your food but that's nothing to do with its cost.

Medicine can be complementary (i.e. alternative therapies used alongside conventional treatments) but is often mistakenly described as complimentary (I guess that's either your therapist treating you for free or telling you how nice you look in the hope that flattery will make you feel better).

Anonymous said...

Don't give tips you don't understand. This article is misleading !! The commenter above me has it correct. When in doubt, Google "define: word" for each word. Kate is dumb.

Ian said...
This comment has been removed by the author.
Ian said...

Dear anonymous, your remarks about Kate are not very complimentary. Nor do they seem to complement her original comment.

Googling define:complimentary produce:

"A complimentary color is the color opposite the color you are using on the color wheel. Orange is the compliment of blue" which is wrong! Those are complementary colours (or colors if you prefer!); unless somebody gives you a can of orange paint free with every can of blue - then orange is complimentary.

and

"Complimentary: having a molecular surface with specifically arranged chemical groups that interact with chemical groups in the surface of another molecule." No, those molecules are complementary (like the complementary base pairs in DNA). They match and pair up so are complementary. They're not free of charge and neither says nice things about the other molecule!

In these instances Google was not our friend. It's quite possible that the distinction may disappear with lack of/mis-use. Many dictionaries now say the different spellings of practise and practice (a verb and a noun respectively) are archaic. As a schoolteacher I often deliberately mis-spell practise/practice in order to annoy the school principal (or is he a principle?) - at least I tell him I'm doing it deliberately!

Anonymous said...

Tip: The "e" in Complement is to Enhance (or Extra as nibornm mentioned); the "e" in complimentary can be remembered as "I" like free stuff or when someone says something nice about me.

Anonymous said...

Your second "e" shoul be an "I".

Alan Cathcart said...

I don't see anything wrong with Kate's original post. However, I don't feel the need to remember more than one rule of thumb - take your pick, depending on how confident you are in your spelling:
--A compliment is complimentary;
--Something that is complementary fills out the complement.