Definition of savannah

From 1986 The Savannahs: Biogeography and Geobotany, by Monica M. Cole (Department of Geography, Royal Holloway and Bedford New College, University of London). Academic Press: London.

pg. 4:
"An understanding of the problems that have beset the formulation of an agreed definition of savannas requires consideration of the origin, historical and present use of the word."

pp. 4-5:
"The term savanna is believed to originate from an Amerindian word which, in a work on the Indies published in 1535, was used by Oviedo y Valdes to describe 'land which is without trees but with much grass either tall or short'. Subsequently Grisebach (1872), Drude (1890) and Schimper (1903) extended its use to include grasslands with trees and thereafter the term was used to describe the mixed trees and grass types of vegetation found in all tropical latitudes."

pg. 5:
In central and southern Africa savanna is used for open deciduous woodlands, including those locally known as miombo, that are composed of fairly tall, mesophyllous trees and a well defined grass stratum, for parklike vegetation comprising grasslands studded with microphyllous trees of low to medium height, for grasslands with scattered clumps of trees or bushes, for treeless grasslands of tall perennial mesophytic grasses and of short annual grasses mixed with perennial grasses with narrow rolled leaves, and for open forms of vegetation composed of scattered low growing microphyllous trees and shrubs and a ground layer of perennial and annual grasses. The term bushveld is used locally for the parklike forms of savanna which together with the low tree and shrub forms are regarded as the most typical savannas."