The word miniature nowadays implies any small object, but it has altered its meaning over the ages. The word derives from the Latin word "minium", meaning red lead or vermillion, the pigment used to paint initial letters on the illuminated manuscripts of the middle ages. The verb "miniare" denotes the process, and the person who did this work was called a "miniator". Thus the word originally described a process and not the object.

The miniature portrait originated in the 16th century, through the union of two separate streams of tradition, one being the illuminated manuscript, the other that of the portrait medal. Portrait Miniature paintings today are usually executed on a small scale, and can be painted in any medium, such as watercolour, oil, enamel or plumbago. Whilst the earliest examples of portrait miniatures are painted on vellum, those of the 18th and 19th century are on ivory.

Silhouette is the term used to describe a small profile. Originally they were known as "shades" or "shadows", partly because they were in fact portraits of the shadows of a face rather than the face itself, and partly because many of the best shades were designed to throw a shadow onto a prepared surface placed behind the outline. The term "silhouette", first used in England in 1835, derives from Monsieur Etienne de Silhouette, a Controller-General whose policies were to restrict expenditure particularly that of the Royal household. The phrase "a la silhouette", came to mean " on the cheap". In comparison with portrait miniatures silhouettes were an in inexpensive medium.