Here, the term ‘fab’ stands for ‘fabrication’.
Meaning of a Fabless Company
A fabless company is a company who takes part only in designing, selling and marketing aspects of hardware and semiconductor chips but not in the fabrication of such products. That's why they are called 'fabless'.
Such fabless companies do not have their own semiconductor fabrication plant / foundry, where devices like integrated circuits are manufactured.
In order to function effectively, semiconductor foundry often requires high production volume. It requires higher capital investment and hence becomes is a very expensive and risky affair in whole.
Therefore, a fabless company generally outsources the fabrication of such chips and hardware from semiconductor foundries.
A Fabless company is also otherwise popularly known as a "Fabless semiconductor company".
Examples of Fabless Companies
Some of the corporates from different countries who are Fabless companies:
In U.S.A. - 3Dlabs, Nvidia, Advanced Micro Devices (AMD), Xilinx, Cirrus Logic, Marvell, Qualcomm, Cadence Design Systems, Synopsys
In U.K. - Dialog Semiconductor, Arm Holdings, BAE System
In Japan - THine Electronics, Toshiba, NEC Semiconductors, Renesas Electronics
In China - Brite Semiconductor, Unigroup, HiSilicon
In Taiwan - MediaTek, Realtek
In Germany - Infineon Technologies AG
In Singapore - Broadcom Ltd.
In Israel - BroadLight