equivalent

Etymology

equi- + -valent. From Latin aequivalentem, accusative singular of aequivalēns, present active participle of aequivaleō (“I am equivalent, have equal power”).

adj

1. Similar or identical in value, meaning or effect; virtually equal.
   To burn calories, a thirty-minute jog is equivalent to a couple of hamburgers.
   A doorknob of whatever roundish shape is effectively a continuum of levers, with the axis of the latching mechanism—known as the spindle—being the fulcrum about which the turning takes place. Applying a force tangential to the knob is essentially equivalent to applying one perpendicular to a radial line defining the lever. 2012-03, Henry Petroski, “Opening Doors”, in American Scientist, volume 100, number 2, pages 112–3
2. (mathematics) Of two sets, having a one-to-one correspondence.
   Finite sets A and B are equivalent sets only when n(A) = n(B) i.e., the number of elements in A and B are equal. c. 2005, P N Gupta Kulbhushan, Comprehensive MCQ's in Mathematics, page 3
   All enumerable sets are equivalent to each other, but not to any finite set. 1950, E. Kamke, Theory of Sets, page 16
   Equivalent sets should, by rights, have the same "number" of elements. For this reason we sometimes say that equivalent sets have the same cardinality. 2000, N. L. Carothers, Real Analysis, page 18
   The equivalence theorem: If both M is equivalent to a subset N₁ of N and N is equivalent to a subset M₁ of M, then the sets M and N are equivalent to each other. 2006, Joseph Breuer, Introduction to the Theory of Sets, page 41
3. (mathematics) Relating to the corresponding elements of an equivalence relation.
4. (chemistry) Having the equal ability to combine.
5. (cartography) Of a map, equal-area.
6. (geometry) Equal in measure but not admitting of superposition; applied to magnitudes.
   A square may be equivalent to a triangle.

noun

1. Anything that is virtually equal to something else, or has the same value, force, etc.
   Our decision about energy will test the character of the American people and the ability of the President and the Congress to govern. This difficult effort will be the "moral equivalent of war" — except that we will be uniting our efforts to build and not destroy. 18 April 1977, Jimmy Carter, President's Address to the Nation on Proposed National Energy Policy
2. (chemistry) An equivalent weight.

verb

1. (transitive) To make equivalent to; to equal.