a structure or object that impedes free movement | the technical aspects of doing something |
any condition that makes it difficult to make progress or to achieve an objective | device consisting of a piece of machinery; has moving parts that perform some function |
anything serving to maintain separation by obstructing vision or access | (philosophy) the philosophical theory that all phenomena can be explained in terms of physical or biological causes |
| a natural object resembling a machine in structure or function |
| the atomic process that occurs during a chemical reaction |