Electronic Design Automation.
Stands for software and tools, algorithms etc. that automate electronic design. In English: stuff that helps you design chips and electronic circuits.
For example: you design the way all components are to be connected, and the software decides exactly where to put them and calculates an efficient wiring between these components. Or, instead of designing the components by hand, you describe them in a HDL and let the EDA tools do the rest.
For a set of EDA standards, you can check out www.eda.org.
Companies delivering these (very expensive) software tools are, among others, Cadence, Mentor and Synopsys.