—v.t. 1. to form or mark differently from other such things; distinguish.
2. to change; alter.
3. to perceive the difference in or between.
4. to make different by modification, as a biological species.
5. Math.to obtain the differential or the derivative of.
—v.i. 1. to become unlike or dissimilar; change in character.
2. to make a distinction.
3. Biol.(of cells or tissues) to change from relatively generalized to specialized kinds, during development.