Source:http://www.hawkdive.com/2016/03/how-to-reinstall-safari-on-my-mac.html#ReinstallSafari

There are multiple ways of reinstalling Safari.If your OS X version has got a new Combo update released and you haven't installed it, Look into the details of Combo update and see if it contains Safari.If it has Safari then installing the Combo will bring Safari back as a fresh new updated version.If your OS X is already updated then follow one of the steps below.

2. Use Pacifist to extract Safari out of the original OS X installation file.

Pacifist is a shareware application that can extract the contents from Mac OS X .pkg package files, .dmg disk images, and .zip, .tar, .tar.gz, .tar.bz2, and .xar archives. This is specially used when a native OS X application becomes damaged and needs to be reinstalled without the hassle of reinstalling all of Mac OS X.

Pacifist is compatible with Mac OS X 10.8 or higher, including Mac OS X 10.11 “El Capitan”. Pacifist requires a 64-bit Intel™ processor.

Download the latest version of Pacifist in zip or disk image format.For users using versions of Mac OS X older than 10.8, download older versions of Pacifist here.Now to Reinstall Safari you need the source image to extract safari from.

You can extract Safari from the following sources.
1. Original OS X installer dmg file.
2. Hidden Recovery Partition on any Mac.

A.) Extract Safari from original OS X installer DMG file.

90% of the times your Mac keeps a copy of the OS X that you downloaded to upgrade your system.This download is by default saved in Application folder.Go to the Application folder and see if you have OS X El Capitan or the current running version of OS X on your Mac.if you do not see it in Application folder, download it from the App store.

1. Open Pacifist and select the first option Open Package.
2. Choose the original OS X installer.dmg file.
3. Then browse through the contents and expand the Application folder to go to the Safari or you can simply type safari in the search box on the top right corner of the windows.
[img]https://2.bp..com/-FHBuL3ST1U0/VvqmlILHp4I/AAAAAAAADds/fLdBIocDNQ42Wha3GQEznVSLawgplDm2A/s1600/Extract%2BSafari%2Busing%2Bpacifist.png[/img]

4. Right-Click or Control-Click the Safari.app and select install.It will install Safari to its default location /Application/Safari.app.

B.) Extract Safari from Hidden Recovery Partition on your Mac.

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