I heard something interesting last night while watching an NCAA game against Kansas State and Xavier (awesome game, by the way; mad props to those K-State players for a game well played). The announcer, towards the end of the game, had said timesout twice in a matter of no more than five minutes. He seemed skeptical about it after he processed what he had said, but then not five minutes later, he said it again and I believe he felt a bit more confident about his saying it.
So, timesout, huh? This is strange because we typically cannot pluralize the first constituent in a compound. Take, for example, doghouse. I don’t know anyone, or any reference, that has said dogshouse (cf. doghouses) is grammatical or even meaningful for that matter. Sure, you can refer to a dog’s house, but that is not the same as the compound structure doghouse which has a head and a complement. Or if you’re inclined to say that doghouse is a transparent compound and therefore transparency plays a role in pluralization, we can take the example honeymoon. Here, too, we cannot say honeysmoon, bur rather honeymoons. So, it does not appear as if transparency has any role whatsoever in this process of pluralization.
So why the timesout? It’s a great question but also interesting regarding the circumstances in which it was said, now that I think back to the moments it was uttered. The announcer was not referring to multiple timeouts being taken, or the wish for multiple timeouts to be taken. No. Instead, he was just referring to a single timeout (something to the effect of, “…he should have called a timesout at that point…“). So the fact that he was even considering a pluralized form is beyond me.
The interesting part in this is that it shows we think, and possibly compute, words morphemically and not as whole-word chunks, especially English compounds. If this were false, then we would not make such mistakes because, in compounds, there would essentially not be any “parts” to be considered; the theory, then, would hold that compounds are monomorphemic elements/constituents in our language.
Edit: Someone in an online thread was trying to make the argument that timesout is indeed grammatical because we can, and apparently do, say runs batted in. Clearly this is an error in judgment. Here they are literally comparing apples to oranges. We cannot compare compound structures to phrases. Once again, as noted above, that’s like saying dog’s house. Yes, it’s a real thing and it’s grammatical, but it’s not comparable because we’re not talking about the same thing. If we want to pluralize a doghouse, then with the logic put forth by that person, we should clearly be able to say, *I painted the dogshouse today (cf. I painted the two, or more, houses that the dogs reside in), and it’s clearly ungrammatical for that intended meaning. Or, for that matter, we should be able to say, *During the game, team X called 4 timesout.