Verilog-A is an industry standard modeling language for analog circuits.
A few commercial applications may export MEMS designs in Verilog-A format.
Verilog-A was created to standardize the Spectre behavioral language in the face of competition from VHDL (an IEEE standard), which was absorbing analog capability from other languages (e.g. MAST).
Open Verilog International (OVI, the body that originally standardized Verilog) agreed to support the standardization, provided that it was part of a plan to create Verilog-AMS — a single language covering both analog and digital design.
This feature is used for example to translate the BSIM Verilog-A transistor models, which are no longer released in C, for use in simulators like ngspice.