staff tree, common name for some temperate members of the Celastraceae, a family of trees and shrubs (many of them climbing forms), widely distributed except in polar regions. These plants typically bear small greenish flowers and have seeds with brightly colored (often orange or scarlet) coats that are exposed when the mature seed pod splits open. Their fruit and brilliant autumn foliage make many species popular as ornamentals. The spindle trees (genus Euonymus) include the wahoo, or burning bush (E. alatus, E. atropurpureas), and the strawberry bush (E. americanus), both of E North America, and a Western species (E. occidentalis) that is also sometimes called wahoo. The East African plant Catha edulis is the source of khat or qat, a popular Yemeni and East African tealike beverage or masticatory made using the leaves. Khat contains cathinone, a stimulant that is similar chemically to amphetamine, and is illegal in the United States. Several members of the family are valued for their medicinal bark as well as for decoration, e.g., the wahoo and the staff trees of the genus Celastrus and the Amazonian chuchuhuasi or chichuá of the genus maytenus. (C. scandens is the climbing bittersweet of North America.) Staff trees are classified in the division Magnoliophyta, class Magnoliopsida, order Celastrales, family Celastraceae.

staff, in musical notation, a set of horizontal lines upon and between which notes are written so as to determine their relative pitch, and in connection with a clef, their absolute pitch. Staffs with several lines survive from the late 9th cent., the lines denoting only pitches. In early attempts at the notation of plainsong, a single line was drawn, with neumes placed above and below it, giving a rough idea of the relative pitches of the tones. Guido d'Arezzo, in the 11th cent., used several lines and put letters on certain of them to indicate their pitch, thus foreshadowing the use of the clef (see musical notation). Four-line staffs proved adequate for plainsong notation and are still employed for that purpose. In 16th-century keyboard music, staffs of six or seven lines were often employed, but later the five-line staff, with ledger lines for pitches outside the range provided for by the staff, became conventional.

Joint Chiefs of Staff, U.S. statutory agency, created in 1949 within the Dept. of Defense. The chairman is the principal military adviser to the President, the National Security Council, and the Secretary of Defense. Members include the chairman, appointed by the President with Senate approval; the chief of staff, U.S. army; the chief of naval operations; the chief of staff, U.S. air force; the commandant of the U.S. Marine Corps, and a vice chairman who manages the Joint Staff. The Joint Chiefs prepare military plans and direct unified and other combat commands under the Secretary of Defense.

Group of military officers that assists the commander of a division or larger unit by helping to formulate and disseminate policy and by transmitting orders and overseeing their execution. It is distinguished from staffs that consist of technical specialists (e.g., medical, police, communications, and supply officers). It appeared in its modern form in the Prussian army in the early 19th century and in other European countries after 1870. The U.S. Army created a general staff in 1903.

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