Learning American English idioms is important for learning to speak English fluently. I wrote a book of the 250 most common idioms that are used in business English. These are idioms I have heard frequently while working in American companies during the last 30 years.
If you can learn one new idiom a day, your English speaking skills will be much higher.
Today’s idiom is:
A rough calculation.
My back-of-the-envelope calculation is that this product will be at breakeven within a year.
Back-of-the-envelope describes when a person grabs any available piece of paper (such as an envelope or piece of scrap paper) to make a quick calculation with a pen or pencil. Since the calculation is done in haste and without a calculator or spreadsheet, the implication is that the calculation is rough, not 100% accurate.
American English has dozens of idioms from the game of baseball. These idioms are common in English, and especially business English. I heard these idioms dozens of time while working and so I have written several blog posts about these very American English idioms. Business English uses many sports idioms because they express ideas about competition, winning and losing.
To give a rough approximation or estimate.
I don’t need to know an exact figure right now. Just give me a ballparkfigure on roughly how many units we can sell per month so I can coordinate with the production team on how much raw material we need to order.
Baseball is played in an enclosed space called a “park”. Other sports are played in enclosed areas called a “stadium”
This idiom refers to a baseball park, which is an enclosed space, but a baseball can be hit and land in many places within the ballpark, and so estimating where a ball might land is an educated guess, an inaccurate estimate or rough approximation within acceptable grounds.
Also, baseball parks in various cities are not all the same size; some are larger than others, in contrast to a football (soccer) or American football field or basketball court that are always the same size in length and width.