the tip of the iceberg

Related to the tip of the iceberg: just the tip of the iceberg

the tip of the iceberg

Only a small, often unrepresentative portion of something much larger or more complex that cannot yet be seen or understood. If congress doesn't vote to extend the debt limit, a government shutdown will be just the tip of the iceberg. The flooding is bad, but we're dealing with just the tip of the iceberg—a huge spate of environmental disasters are on the horizon because of climate change.
See also: iceberg, of, tip
Farlex Dictionary of Idioms.

tip of the iceberg

Fig. only the part of something that can be easily observed, but not the rest of it, which is hidden. (Referring to the fact that the majority of an iceberg is below the surface of the water.) The problems that you see here now are just the tip of the iceberg. There are numerous disasters waiting to happen.
See also: iceberg, of, tip
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

tip of the iceberg

Superficial evidence of a much larger problem, as in Laying off a hundred workers is only the tip of the iceberg. This idiom alludes to the structure of an iceberg, most of whose bulk lies underwater. [Mid-1900s]
See also: iceberg, of, tip
The American Heritage® Dictionary of Idioms by Christine Ammer.

the tip of the iceberg

or

the tip of an iceberg

COMMON
1. If something is the tip of the iceberg or the tip of an iceberg, it is a small part of a very large problem or a very serious situation. We get about 2,000 complaints every year and that's just the tip of the iceberg. Figures show that there have been 700 official burglaries throughout the area, but police believe this is the tip of the iceberg.
2. If something is the tip of the iceberg or the tip of an iceberg, it is a small part of something large. These surveys are only the tip of an iceberg of continuing study. Note: People often use an adjective before iceberg to show what sort of thing it is. These songs are just the tip of the creative iceberg. Note: Only a very small part of an iceberg is visible above the water. About nine-tenths of it is below the surface.
See also: iceberg, of, tip
Collins COBUILD Idioms Dictionary, 3rd ed.

tip of the iceberg

A small evident part or aspect of something largely hidden.
See also: iceberg, of, tip
American Heritage® Dictionary of the English Language, Fifth Edition.

tip of the iceberg, (only) the

A small and superficial manifestation of a much larger (and often worse) situation. Icebergs are large, floating masses of ice detached from a glacier and carried out to sea; the bulk of their mass is below the water’s surface. This metaphor dates from the mid-twentieth century. Michael Gilbert used it in The Etruscan Net (1969): “I think, to employ a well-known metaphor, that all we can see at the moment is the tip of the iceberg.”
See also: of, tip
The Dictionary of Clichés by Christine Ammer
See also:
  • be the tip of the iceberg
  • iceberg
  • just the tip of the iceberg
  • the tip of an iceberg
  • tip of the iceberg
  • tip of the iceberg, (only) the
  • it's a (type of person) thing
  • it's a... thing
  • be/go against the grain
  • go against the grain
References in periodicals archive
Of course, this is just the tip of the iceberg. The same powerful mind control has apparently been applied to the entire western world, making us believe that nonsensical diet fads - as opposed to healthy eating and exercise - actually work
Slim pickings
This heinous murder is just the tip of the iceberg. The Gambian people have been suffering from a culture of silence for years.
Poor Gambia
This is only the tip of the iceberg. According to Pendergrast, CDM Technologies plans to build software agents into the scanners to scan cargo and hazardous material containers, differentiating between the two.
SDDC capitalizes on small hardware to make big improvements; big things come in small packages ... and for the better
With the federal government auditing less than 1 percent of E-rate recipients, these cases may be just the tip of the iceberg in a program that has spent $13 billion to date.
School net scams: no tech firm left behind
But even if adoption offers an apt metaphor for the history of the nation itself, these questions are only the tip of the iceberg. Adoption in America testifies that we still have a long way to go before exhausting such basic questions as who children are, what families have been, and how each has been made and remade over time.
Adoption in America: Historical Perspectives
What we have seen to date is probably just the tip of the iceberg when we think of what may be possible, even probable, in the not-so-distant future.
Gustafson's technology gaining attention
As Morandi's trial unfolded in the summer and early fall, however, it became apparent that his little astrological judgment was no more than the tip of the iceberg. Under Morandi's abbacy, San Pressede was the epicenter of a hubbub of illicit activity, including, besides the perhaps obvious sexual shenanigans of poorly supervised monks, the copying and circulation of prohibited books, astrological consultations, and magical operations.
Brendan Dooley. Morandi's Last Prophecy and the End of Renaissance Politics
On the contrary, I would say they may be 100% accurate and only the tip of the iceberg when it comes to the unfair practices being employed by some of the foreign casting sources.
We aren't car salesmen, are we?
"These days the game is the tip of the iceberg when it comes to media exposure.
Insurers sit on sidelines during Super Bowl ad blitz. (Property/Casualty: Marketplace)
"This water ice may be just the tip of the iceberg," says Titus.
Mars reveals more frozen water. (Astronomy)
The story of the kidnapping and rescue, gripping as it is, is only the tip of the iceberg. Listeners will be introduced to the volatile religious/political situation that has emerged since the breakup of the USSR.
Over the Edge: the True Story of Four American Climbers' Kidnap and Escape in the Mountains of Central Asia
Supporting the efficient use of nursing time for ordering and tracking medications, researching drug information and communicating with the pharmacy and prescribers are only the tip of the iceberg of advantages offered by connectivity.
The IT revolution in LTC pharmacy: it promises more control of one of the fastest-growing costs in long-term care. (Feature Article)
And the proliferation of non-dairy desserts like Tofutti, Soy Delicious, and Rice Dream Bars is just the tip of the iceberg.
VRG celebrates our 20th anniversary. (Note from the Coordinators)
According to Iowa Senator Tom Harkin, some 15,000 deaths are "known to be attributable to those nuclear tests," and that may be just "the tip of the iceberg."
Mercury falling. (E Word)
And that's only the tip of the iceberg. After last year's drought, it's an embarrassment of riches.
From the editor