The phrase "microphone input" refers to a port or connector on a device like a computer or sound system, where you can plug in a microphone. It is the way to connect a microphone and use it to capture and record sound. Full definition
Ports include two USB 3.1 Type - C, three regular USB, one DisplayPort, one HDMI, and 3.5 mm jacks for microphone input for and speaker audio output. (mobilesyrup.com)
Up top are the mini-HDMI port and the connector port for charging the tablet and syncing data, and at the right rear are the headphone jack (which doubles as an external microphone input) and a USB port (which will work for input devices such as a mouse, and for flash devices such as memory drives). (pcworld.com)
In Stifled, the sounds made by your in - game character and yourself through microphone input reveal the otherwise hidden world through «echolocation». (stifledgame.com)