Multi-Select Dropdown with size of 1

Is there any way of creating a combo box (<select>) with a开发者_运维百科 size of 1? All the examples I can find allow for multiple selects but with a number of options visible at any one time. If this cannot be accomplished with bog standard HTML is it possible in a JS library such as JQuery?

EDIT: My post does not answer the question, but the comments might clarify the question.

What you want is to set the attribute size to 1, i.e.:

<select size="1" name="...">
    <option value="...">...</option>
    ...
</select>

I'm afraid that would be usability nightmare. What is the more general goal you are trying to achieve? I'm sure better solutions already exist.

I could guess you need something like tag editor widget.