A gate equivalent (GE) stands for a unit of measure which allows specifying manufacturing-technology-independent complexity of digital electronic circuits.
For today's CMOS technologies, the silicon area of a two-input drive-strength-one NAND gate usually constitutes the technology-dependent unit area commonly referred to as gate equivalent.
A specification in gate equivalents for a certain circuit reflects a complexity measure, from which a corresponding silicon area can be deduced for a dedicated manufacturing technology.
In digital circuit design, a dedicated standard cell library is employed for each manufacturing technology (e.g., CMOS).
Basically, a two-input drive-strength-one NAND gate in CMOS technology consists of four transistors.