1774, partial loan-translation of Dutch ijsberg, literally "ice mountain," from ijs "ice" (see ice (n.)) + berg "mountain" (see barrow (n.2)). An earlier term was sea-hill (1690s). Phrase tip of the iceberg, in a figurative sense, first recorded 1962. Iceberg lettuce attested from 1893.
A massive body of floating ice that has broken away from a glacier or ice field. Most of an iceberg lies underwater, but because ice is not as dense as water, about one ninth of it remains above the surface.
Only a hint or suggestion of a much larger or more complex issue or problem: “The money missing from petty cash was only the tip of the iceberg of financial mismanagement.” This phrase alludes to the fact that the bulk of a floating iceberg is concealed beneath the water, leaving only a small portion, its tip, visible above.
A large piece of ice that has broken away from a glacier at the shore and floated out to sea.
Most of the ice in an iceberg is underwater, leaving only the “tip of the iceberg” visible — a fact that is often alluded to in discussions of subjects in which the most important aspects are hidden from view.
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]