A recent discussion on ADS-L combined three themes of enduring interest on this blog: conversion of N to V and vice versa; the alternation in spelling between separated, hyphenated, and solid spelling of compounds (see recent discussion by Mark Liberman on Language Log about the V + Prt compounds build out, build-out, and buildout); and the inclination to externalize inflection in compounds that have come to be viewed as unitary lexical items (see a collection of V/N = V + Prt examples here).
The ADS-L discussion was about mouse over / mouse-over / mouseover, which I’ll refer to as MO in what follows.
Conversion. MO occurs both as a N and a V, and it’s not clear to me which is historically original. From Wikipedia, with the N:
In computing, a mouseover, mouse hover or hover box refers to a section of a computer user-interface that is raised when the user moves or “hovers” the pointer over a particular area of the GUI. The technique is particularly common in web browsers where the URL of a hyperlink can be viewed in the status bar.
This gives a N + Prt (‘a (computer) mouse (poised) over some area of text’) or N +N (‘the hover(ing) of a (computer) mouse over some areaof text’) analysis to the N, but whatever the origins, current uses clearly have the Prt over (related to the P over) rather than the nominalized V hover. And the N seems almost always to be spelled solid, as mouseover.
Punctuation. Things are more complicated with the V MO, ‘place a (computer) mouse) over some area of text’, which occurs (in considerable numbers) in all three spellings:
[HYPHENATED] Conversion of 2D to 3D can be started by clicking on the “Start” button. After the successful conversion of the video file, user needs to mouse-over the image and then click play to view the video in 3D format. (link)
[SOLID] I have a shortcode blog list which contains an image, title, text, read more for each post. When I mouseover the image in the blog list I see a link to /wp-content/uploads/image path etc (link)
The usual progression of punctuation is from separated to hyphenated to solid, as the compound is seen to be more fixed, formulaic, or idiomatic.But, as Mark Liberman said in his Language Log piece on build + out,
The spelling of such compound nouns — at least the question of space vs. hyphen vs. nothing — is one of the last unconquered bastions of English orthographic liberty. Particular publications may attempt to impose particular patterns for the spelling of particular compounds in particular contexts, but freedom stubbornly persists, even in the works of individual writers.
… That said, there are two factors that obviously play a role in our compound-spelling choices. First, more familiar combinations tend to be hyphenated or written solid — and as a compound becomes lexicalized, it is more closely combined more often. And second, there’s a tendency for nominal structures of the form [[X Y] Z] to be written X-Y Z, in order to make the structure clearer to readers.
In general, the punctuational issue is of little linguistic significance, though commenters often treat it as profoundly important.
Externalization. Reaction to the solid spelling mouseover, especially for the V, has been notable; some people are offended by it. They see, quite correctly, that the solid spelling invites a reinterpretation of the V as an indivisible lexical item, so that inflection would appear finally rather than internally: the inevitable (she) mouseovers, mouseovered, etc.
But if he mouseovers his clock time, this is what he will see and realize he was mistaken: … (link)
Navigation buttons are blinking when pressed or mouseovered (link)
Not a huge number of examples, but enough to make it clear that these forms make sense to a lot of people.
The ADS-L discussion harked back to another example of externalization of inflection for V = V +Prt, log in. See Mark Liberman’s discussion of loginned on LLog, here.