in a general sense, an appellation given to whatever is composed or made up of different things; thus we say, a compound word, compound sound, compound taste, &c. Compound differs from complex, and stands opposed to simple.

Compound Interest, called also interest upon interest, is that which is reckoned not only upon the principal, but upon the interest itself forborne, which thereby becomes a sort of secondary principal.

Compound Motion, that motion which is effected by several conspiring powers. Powers are said to conspire if the direction of the one be not quite opposite to that of the other, as when the radius of a circle is conceived to revolve about a centre, and at the same time a point to move straight along it.

Compound Numbers, those which may be divided by some other number besides unity, without leaving any remainder; such as 18 and 20, the first being measured by the numbers 2, 6, 9; and the second by the numbers 2, 4, 5, 10.

Compound Ratio is that which the product of the antecedents of two or more ratios has to the product of their consequents. Thus 6:72 is in a ratio compounded of 2 to 6, and of 3 to 12.