Reverse operation of mount. Instructs the operating system that the file system should be disassociated from its mount point, making it no longer accessible.(verb)
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Use "unmount" in a sentence
"Though Android is clearly one of Alex's core strengths, it may also prove to be a weakness because its techie quirks may flummox average consumers (for example, the need to "unmount" a memory card before removing it, or to go into the notifications field and mount the e-reader as a USB device when connected to your PC)."
"PS is "umount / here" a typo for "unmount"? umount command, you can also see what's still mounted by typing; mount"
"To unmount the image, head into My Computer and eject the drive, or right-click on the actual image file and unmount it from there."