Wiktionary
n. Any device used to store and retrieve digital information that is manufactured using integrated circuit technology
Wikipedia
Semiconductor memory is an electronic data storage device, often used as computer memory, implemented on a semiconductor-based integrated circuit. It is made in many different types and technologies.
Most modern semiconductor memory devices are implemented allowing random access, which means that it takes the same amount of time to access any memory location, so data can be efficiently accessed in any random order. This contrasts with data storage media such as hard disks and CDs which read and write data consecutively and therefore the data can only be accessed in the same sequence it was written. Semiconductor memory also has much faster access times than other types of data storage; a byte of data can be written to or read from semiconductor memory within a few nanoseconds, while access time for rotating storage such as hard disks is in the range of milliseconds. For these reasons it is used for main computer memory (primary storage), to hold data the computer is currently working on, among other uses.
Shift registers, processor registers, data buffers and other small digital registers that have no memory address decoding mechanism are not considered as memory although they also store digital data.
Usage examples of "semiconductor memory".
The CRAY had a random access semiconductor memory capable of transferring up to 320 million words per second, or the equivalent of about 2,500 300-page books.
These failures are caused by trace amounts of radioactive elements present in the packaging material used to encapsulate the silicon devices which, upon radioactive decay, emit high energy alpha particles that upset the logic states of the semiconductor memory.