Given how common the compound word "child care" is, you would think we could agree on whether to spell it as one word or two.
And that's just the tip of the compound iceberg.
University of Michigan English Professor Anne Curzan says That's What They Say listener Adam e-mailed a question about "fundraise."
Is it one word, two words, or do you put a hyphen in it, Adam wondered.
"I wish I could give Adam a definitive answer of what to do with all compounds, but it depends on which words we're talking about," Curzan says.
"I dug into 'fundraise,' and had not realized how new a verb it is. Older are the nouns 'fundraiser' and 'fundraising,' and from that we get the verb 'fundraise.' Historically, with fundraiser, it's been more common with the hyphen, but as of the early 2000s, the one-word spelling with no hyphen has become more common for all three forms, so I would say in that case, one word."
But then Curzan thought about another example: "Child care."
"I was sending an e-mail, and suddenly I thought, 'Is child care one word or two? So I dug in and tried to figure it out. In that case, the two-word spelling is still more common, but the one-word spelling is on the rise."
Does anyone really care about the hyphen anymore?
"I think they do," Curzan says. "In 2007, when the Shorter Oxford English Dictionary published its new edition, it removed 16,000 hyphens, and this made headlines.
With some of those words, they were put into one word: pigeonhole, bumblebee, crybaby, lowlife. But some became two words: test tube, ice cream, water bed. In other words, there wasn't one pattern once you got rid of the hyphen."
So how do we know when a compound word is a compound word? Again, it depends, Curzan says.
"When two words appear next to each other, like 'blue bird,' is it a compound or just two words next to each other? If I'm looking at a group of birds, and I'm trying to distinguish the red bird from the blue bird, that's not a compound. But if I'm talking about bluebirds, that bluebird is a compound."
Stress patterns also offer a clue, Curzan says.
"When it's a compound, the stress will tend to occur on the first word, and the second word will carry light stress."
Curzan says Adam, also wondered about "cab driver."
Two words is most common, but Curzan says you'll find instances of it as one word, but almost nobody is spelling it with a hyphen.