Definition of button bar
: a collection of buttons (see 1button 3d) on a computer screen arranged in a single strip or block <This is the part that's not very obvious: There is no visible button to attach a photo. In the body of the email message, you need to touch the screen where you want to insert the photo. If you hold your finger on the screen for more than one second, you should see a black button bar appear. — Jim Rossman>
First Known Use of button bar
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