# What is a better word for “exponentially”?

I often hear news reports of rapidly increasing problems use the word "exponentially" for emphasis. For example, tonight's BBC America World News included a segment on the growing Syrian refugee problem, saying the number of refugees was "increasing exponentially".

Now clearly this usage is not consistent with mathematically accurate usage and though I'm sure most understand the intent, it still bothers me.

For reference, the number of registered Syrian refugees increased from 471,808 on 2012-12-31 to 2,241,100 on 2013-12-13. Neither "five-fold increase" nor "quintupling" seem to have the same impact.

Can anyone suggest an alternative word that is not so mathematical in nature to describe such an increase? Of course, I'm looking for a word to describe future growth, not past.

There is no single word that is close to exponential. You are correct, of course, that the growth is not exponential. But exponential connotes a rapid and increasing rate of growth. In reality, your example might more closely represent a sigmoidal growth curve, but we don't generally say that of growth.

The closest words I can think of would be explosive, sudden, dramatic, rapid, mushrooming, snowballing, escalating, rocketing, skyrocketing, accelerating.

• I happen to prefer explosively. – tchrist Dec 14 '13 at 13:50
• @tchrist: I think there's a very big difference in the connotations of figurative explosively and exponentially. Presumably everyone would agree the most important thing about explosive is that it happens very fast. That requires us to have a subjective and context-specific understanding of what exactly words like fast/slow are relative to. But to me at least, exponential doesn't really have any such connotation. It simply means that unless the growth pattern changes, eventually, something will become infinite. – FumbleFingers Dec 14 '13 at 14:17
• @FumbleFingers There are many kinds of non-linear growths, not just exponential. When each term differs from the previous one by +2 (linear) or *2 (exponential) or **2 (superexponential) respectively, then linear growth works like 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, ...; exponential growth works like 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, ...; and superexponential growth works like 2, 4, 16, 256, 65536, 4294967296, 18446744073709551616, 340282366920938463463374607431768211456, 115792089237316195423570985008687907853269984665640564039457584007913129639936, .... – tchrist Dec 14 '13 at 16:20
• The looser sense is given as the primary denotation by ODO: exponential [adjective] 1 (Of an increase) becoming more and more rapid: the social security budget was rising at an exponential rate – Edwin Ashworth Jul 17 '15 at 12:56

Perhaps dramatically

(of an event or circumstance) sudden and striking: a dramatic increase in recorded crime

"Exponential" may be a perfectly accurate word, although it would require more than two points to confirm. It's not correct to say it can't be exponential - there are many everyday examples of exponential growth - for instance compound interest in a savings account. However, exponential growth cannot go on indefinitely, because something will eventually force it to stop - usually in a fairly dramatic way. It is entirely possible that the Syrian refugee growth is exponential at this point, but it clearly cannot continue exponentially for an indefinite period.

If you still don't like "exponential" then Susan's suggestions are excellent.

• +1 for making the key point that exponential growth cannot go on indefinitely. I have a savings account currently paying 0.05% interest, which simply adds a few pence to the balance every month. Obviously this represents "exponential growth", since compound interest at any rate is the archetypal example thereof. OP's problem simply seems to turn on the fact that he inappropriately associates the subjective concept of "rapid" with "exponential". – FumbleFingers Dec 14 '13 at 14:28
• @FF: It's an accepted looser definition. OP wrongly associates the BBC (looser) usage with the mathematical (stricter) definition, saying that the BBC usage is wrong. It's not, it's in a different register from the one he is demanding (cf hurricane vs hurricane). Of course, nothing in nature increases in an exactly exponential (strict definition) way for long. – Edwin Ashworth Dec 14 '13 at 16:21

Considerably could be used. Same effect without the mathematical connotations.

• Hey Brandi. I'm betting you got a downvote because you didn't quote the definition of considerably which supports this usage, or refer to an external authority to back up your answer. (Unlike some other Q&A sites, like Yahoo! answers, SE doesn't solicit opinions; answers are expected to be substantial and substantiated.) – Dan Bron Apr 7 '15 at 17:12

Non-linearly could likely be more correct, mathematically speaking. Non-linearly is a generalisation of a type of growth which includes "exponential, parabolic, logarithmic, etc", but obviously excludes "linearly" (ie, in a straight line). As an alternative that is a little less mathematically precise than "exponentially".

• There are all kinds of nonlinear growths apart from exponential growth. – tchrist Dec 14 '13 at 20:05