Aptitude \Apt"i*tude\, n. [F. aptitude, LL. aptitudo, fr. L. aptus. See Apt, and cf. Attitude.]

1. A natural or acquired disposition or capacity for a particular purpose, or tendency to a particular action or effect; as, oil has an aptitude to burn.

He seems to have had a peculiar aptitude for the management of irregular troops. --Macaulay.

2. A general fitness or suitableness; adaptation.

That sociable and helpful aptitude which God implanted between man and woman. --Milton.

3. Readiness in learning; docility; aptness.

He was a boy of remarkable aptitude. --Macaulay.

Source: Webster's Revised Unabridged Dictionary (1913)