Defn: A partition; a septum; specifically, the folds of the pleura (and the space included between them) which divide the thorax into a right and left cavity. The space included between these folds of the pleura, called the mediastinal space, contains the heart and gives passage to the esophagus and great blood vessels.
MEDIATE Me"di*ate, a. Etym: [L. mediatus, p. p. of mediare, v. t., to halve, v. i., to be in the middle. See Mid, and cf. Moiety.]
1. Being between the two extremes; middle; interposed; intervening; intermediate. Prior.
2. Acting by means, or by an intervening cause or instrument; not direct or immediate; acting or suffering through an intervening agent or condition.
3. Gained or effected by a medium or condition. Bacon. An act of mediate knowledge is complex. Sir W. Hamilton.
MEDIATE
Me"di*ate, v. i. [imp. & p. p. Mediated; p. pr. & vb. n. Mediating.]
Etym: [LL. mediatus, p. p. of mediare to mediate. See Mediate, a.]
1. To be in the middle, or between two; to intervene. [R.]
2. To interpose between parties, as the equal friend of each, esp. for the purpose of effecting a reconciliation or agreement; as, to mediate between nations.
MEDIATE
Me"di*ate, v. t.
1. To effect by mediation or interposition; to bring about as a mediator, instrument, or means; as, to mediate a peace.