Type fdisk /dev/xxx and press enter, where xxx is a device, such as /dev/sda or /dev/sdb.

[root@server1 ~]# fdisk /dev/sdb

Type d and press enter to delete a partition.

Command (m for help): d

Something like this should be displayed.

Selected partition 1
Partition 1 is deleted

Type w and press enter to write the changes.

Command (m for help): w

Use the partprobe command to update the system to recongize the change.

~]# partprobe