Words have their trends no less than do spring fashions. You may see Tangerine Tango (the Pantone Color of the Year for 2012) all over this season – well, on two or three people, anyway. And you may find you hear or see the same turn of phrase everywhere.
That's what an e-mail correspondent reports has happened to her. After not hearing it "for AGES" (the all caps are all hers) she keeps running into the idiom "to tease out."
A recent Monitor article noted, "Teasing out trends in extreme weather and identifying global warming's fingerprint are challenging...."
And in a blog post commenting on the work of Michael Pollan ("The Botany of Desire," inter al.), she ran across this: "Pollan, moreover, can be a masterful stylist when it comes to teasing out nature's more subtle interrelations."
I'll add a third example, from an essay that ran in a California newspaper: "How does an artist coax a multi-dimensional image from a bare canvas? How do hand and eye tease out the shades and the shadows, the light and dark that go into the mystery of art?"
In the beginning, teasing was part of the textile trade. The Online Etymology Dictionary reports that our verb tease comes from an Old English verb meaning to pull or to pluck apart. "The original sense is of running thorns through wool or flax to separate, shred, or card the fibers."
The phrasal verb tease out is used transitively. It refers to a way of acting on some object. One "teases out" wool. One (gently) teases out the roots of a pot-bound plant one is transplanting into the ground.
A definition from Macmillan's dictionary takes us into the realm of the metaphorical: To tease out is "to succeed in discovering something difficult, complicated, or secret."
"To obtain by or as if by disentangling or freeing with a pointed instrument" is how Merriam-Webster's online dictionary defines this usage, which it dates to 1828.
When one speaks of teasing out the data to identify the important trends, the data is (are?) the metaphorical wool – the thing acted on. The data may be indeed fuzzy. But as teasing wool eliminates the burrs and pebbles and other extraneous matter, so teasing out data may involve eliminating data points that only distort the picture.
In this second sense, what is acted on is something that is "obtained," the "findings," in other words. You tease out the data (wool) to tease out the larger meaning (burrs, pebbles, etc.). What is to be discarded in the literal sense of teasing is what is sought out in the metaphorical sense.
Thus, a foreign exchange analyst commenting on a new report about debt woes in Spain writes, "Let's tease out some of the highlights." He might have written, "Let's tease out the report to get some of the highlights." But it's easy to see why he made the elision he did. This is how language evolves. Meanings get extended, and metaphors shift.
By the early 17th century, tease had acquired a sense of "vex, worry, annoy." Performed on wool, teasing was a first step to creating useful fabrics for clothing and other purposes. Performed on a person (by running metaphorical thorns through his hair?) teasing would be fairly harsh action. The meaning softened ("I was only teasing") but then picked up a sense of enticement to coming attractions – a television producer "teasing" the plotlines of his show's new season, for instance.
There's a lot more to tell. But I may just have to tease you with that.