integral

Concise Oxford English Dictionary © 2008 Oxford University Press:
integral

▶adjective /ˈɪntɪgr(ə)l, ɪnˈtɛgr(ə)l/ 

• 1 necessary to make a whole complete; fundamental.

  ■ included as part of a whole.

  ■ having all the parts necessary to be complete.

• 2 Mathematics of or denoted by an integer or integers.

▶noun /ˈɪntɪgr(ə)l/ Mathematics a function of which a given function is the derivative, and which may express the area under the curve of a graph of the function.

– derivatives
integrality noun,
integrally adverb.

– origin C16: from late L. integralis, from integer (see integer).

usage: There are two possible pronunciations for integral as an adjective : one with the stress on the in- and the other with the stress on the -teg-. In British English, the second pronunciation is sometimes frowned on, but both are broadly accepted as standard.