What's the proper name of that symbol to collapse/expand nodes in a directory tree?

I'm pretty embarrassed to admit I don't know this one...I just realized I've always just described it, not actually named it :)

So, that folder/directory collapse/expand symbol thingy, you know, this one:

Screenshot containing symbol in question

What is it called?

Some file managers depict it as a plus/minus sign, others as a triangle with changing orientation and/or color, and other file managers have yet different symbols for it.

But I'm looking for the generic name of the functionality.

My Google searches have so far all resulted in "plus/minus symbol" or "folder tree triangle" or similar, all referring to the specific icon or symbol used to represent the functionality (and, as usual, using the terms "folders" and "directories" interchangeably).

But there just has to be a proper name for it!

Rody Oldenhuis

Posted 2013-08-29T09:38:52.637

Reputation: 352

This answer is obviously incorrect, so I'm posting it as a comment - but in almost all software I've used, it's known as a caret. – dgo – 2014-07-01T23:46:49.670

@user1167442: caret is the name of the ">" symbol. When you click on it, they often replace that with a chevron (too lazy to look up the Ascii code to include it here, but it's the caret rotated so it points down). But that's the symbol they sometimes use for the function, not the name of the function, itself. – fixer1234 – 2016-06-15T19:01:41.110

1It's a tree view widget known as an expander arrow. – martineau – 2013-08-29T10:36:22.080

@martineau: is that true also for the "old fashioned" plus/minus signs? – Rody Oldenhuis – 2013-08-29T11:12:42.167

2I suppose a more generic term would be an expander control or indicator, neither of which exactly roll off the tongue. – martineau – 2013-08-29T15:00:12.240

Answers

The Microsoft UX Guide mentions these UI elements in the section about Progressive Disclosure Controls.

The element shown in your screenshot is amazingly named rotating triangle. Their counterparts are named plus and minus controls:

enter image description here

Both elements are also discussed in more detail on later pages, but the name is always the same.

enter image description here

The name of another UI element that is often associated with collapsible containers is the chevron, which is also pictured in the first screenshot. But this element is used in a different context.

Der Hochstapler

Posted 2013-08-29T09:38:52.637

Reputation: 77 228

Generic term is "disclosure widget". Third parties will of course use their own variations though.

https://en.wikipedia.org/wiki/Disclosure_widget

JoeDuncan

Posted 2013-08-29T09:38:52.637

Reputation: 131

Please quote the essential parts of the answer from the reference link(s), as the answer can become invalid if the linked page(s) change. – DavidPostill – 2016-06-15T20:36:52.497

Technically spoken, this symbol is a button to collapse/expand the TreeViewControl. Microsoft not provided any collapsible control for Windows applications, if we required Collapsible control we have to develop our own control with our own functionality.

So I would say the most generic name of this control is "Collapsible Control" :)

duDE

Posted 2013-08-29T09:38:52.637

Reputation: 14 097

hmmm...do you happen to have an authorative reference for that? :) – Rody Oldenhuis – 2013-08-29T10:16:15.107

I'm duDE, I dare it ;) Thanks for up voting, dude! – duDE – 2013-08-29T10:21:28.030

I call the icons the expand icon and the collapse icon, and the control with which the icons are associated the expand/collapse control. I'm not aware of a standard cross-platform name for it, although duDE's Microsoft-based answer seems entirely reasonable.

user340406

Posted 2013-08-29T09:38:52.637

Reputation: 11