(physics, chemistry, dated) Pedantic form of mass number. Symbol: A.

(finance, investing) An employee or department that is responsible for implementing a fund's investing strategy and managing its portfolio trading activities.

(number theory, recreational mathematics) A magic square of order n containing the numbers 1 to n² and where each 2 × 2 subsquare sums to 2s, where s = n² + 1, and all pairs of integers distant n/2 along a (major) diagonal sum to s.

plural of pandiagonal magic square

(number theory, recreational mathematics) A magic square using the decimal digits of the reciprocal of a prime number.

plural of prime reciprocal magic square

plural of most-perfect magic square

(number theory, recreational mathematics) A magic square with the additional property that the broken diagonals also summate to the magic constant.

Used to form nouns having the sense of "a comrade or fellow with whom what is denoted by the noun is shared".

plural of magic money tree