Holland is a geographical region and former province on the western coast of the Netherlands. From the 10th to the 16th century, Holland proper was a unified political region within the Holy Roman Empire as a county ruled by the counts of Holland. By the 17th century, the province of Holland had risen to become a maritime and economic power, dominating the other provinces of the newly independent Dutch Republic.

The area of the former County of Holland roughly coincides with the two current Dutch provinces of North Holland and South Holland into which it was divided, and which together include the Netherlands' three largest cities: the capital city (Amsterdam), the home of Europe's largest port (Rotterdam), and the seat of government (The Hague). Holland has a population of 6,583,534 as of November 2019, and a population density of 1203/km².

The name Holland has frequently been used informally to refer to the whole of the country of the Netherlands. This casual usage is commonly accepted in other countries, and is even employed by many Dutch themselves. However, some in the Netherlands (particularly those from regions outside Holland or the west) find it undesirable or misrepresentative to use the term for the whole country. In January 2020, the Netherlands officially dropped its support of the word Holland for the whole country, which included a logo redesign that changed "Holland" to "NL".

The name Holland first appeared in sources for the region around Haarlem, and by 1064 was being used as the name of the entire county. By the early twelfth century, the inhabitants of Holland were called Hollandi in a Latin text. Holland is derived from the Old Dutch term holtlant ('wood-land'). This spelling variation remained in use until around the 14th century, at which time the name stabilised as Holland (alternative spellings at the time were Hollant and Hollandt). A popular but erroneous folk etymology holds that Holland is derived from hol land ('hollow land' in Dutch), purportedly inspired by the low-lying geography of the land.

"Holland" is informally used in English and other languages, including sometimes the Dutch language itself, to mean the whole of the modern country of the Netherlands. This example of pars pro toto or synecdoche is similar to the tendency to refer to the United Kingdom as "England", and developed due to Holland's becoming the dominant province and thus having the majority of political and economic interactions with other countries.

Between 1806 and 1810 "Holland" was the official name for the country as a whole, after Napoleon made his brother Louis Bonaparte the monarch of the Kingdom of Holland.

The people of Holland are referred to as "Hollanders" in both Dutch and English, though in English this is now unusual. Today this refers specifically to people from the current provinces of North Holland and South Holland. Strictly speaking, the term "Hollanders" does not refer to people from the other provinces in the Netherlands, but colloquially "Hollanders" is sometimes used in this wider sense.

In Dutch, the word Hollands is the adjectival form for Holland. Hollands is also colloquially used by some Dutch people in the sense of Nederlands (the Dutch language), occasionally with the intention of contrasting with other types of Dutch people or forms of the language—for example Limburgish, the Belgian varieties of the Dutch language ("Flemish"), or even any southern variety of Dutch within the Netherlands itself.