NEW YORK (MainStreet) – When you hear the term “family car,” what springs to mind?

Is it a utilitarian, reliable sedan? Is it an old station wagon? Is it dad's minivan? Mom's huge '90s SUV? The small crossover you use as a school and soccer shuttle? Increasingly, it's whatever a U.S. family needs it to be.

Each year, automotive publications release their list of best family cars in an attempt to define what the term “family car” means that year. Kelley Blue Book needs 15 vehicles to illustrate its ideas about family transportation. Edmunds needed to consult Parents magazine just to whittle its own definition to 10 vehicles. Each is a melange of compacts, crossovers, minivans, midsize sedans, SUVs and pickups representing a marketplaces just as diverse as its needs.

“Family vehicles aren't a one-size-fits-all proposition,” says Aaron Lewis, spokesman for Edmunds.com. “A family of five's needs are different for those of a family of three, or the needs of a single-parent household. So the lineup of family cars is diverse, and is just as likely to include compact cars and sedans as it would SUVs and minivans.”

All that said, there are a few common threads that run through the tiny, lower-priced Mazda3 and Ford Fiesta on Edmunds' list and the hulking Chevrolet Tahoe SUV and Ford F-150 and Ram 1500 pickups among KBB's choices. For Jason Allan, managing editor of features for Kelley Blue Book’s KBB.com, it all comes down to value, versatility and safety.

“For young families, versatility can mean the ability to install and remove car seats with ease,” he says. “Years later, that same family might require three rows of seats and the ability to adjust to changing passenger and cargo configurations on the fly.”

A car that can grow with a family's needs is certainly high on U.S. car buyers' shopping lists this year. Sales of crossovers are up 10.3% through February, according to MotorIntelligence, and the 590,000 sold in the first two months of 2015 are the most of any vehicle type. The venerable midsize car comes in a distant second, but still holds its ground with 498,000 vehicles sold. Both have proven themselves reliable options for shuttling around families and their stuff, with the Toyota Camry, Nissan Altima, Ford Fusion, Toyota RAV4, Honda CR-V and Honda Accord ranking among the Top 10 vehicles sold this year.

“Whether you're carrying a lot of people, a lot of their stuff, or a lot of both, your family car needs to get it all where you need to go,” says Brandy Schaffels, automotive industry analyst and chief editor of automotive site AskPatty.com. “Young families need room for strollers and car seats, others need room for their kids' backpacks and sports gear.”

That “value” proposition is where it gets a bit trickier. The small-car category is the fastest-growing outside the truck and SUV category after seeing a 5.4% uptick in the first two months. The sale of small cars still lags behind midsize cars and crossover SUVs, but the 446,000 small cars sold this year outpaces pickup trucks (351,000) and every other SUV category combined (246,000). Meanwhile, thanks to that downturn in gas prices this year, the sale of non-crossover SUVs spiked 30% through February. Price and fuel economy can add up to value for some families, but reliability and resale value are just as important to others.

“Value is also important to families, but can be trickier to assess,” Allan says. “While a vehicle’s MSRP and fuel economy ratings are printed right on the window sticker, depreciation is typically the biggest vehicle expense in a full ownership cycle. When weighing two or more vehicles, in many cases it can cost less in the long run to pay more for the one with the best resale value.”

That third category, safety, is basically being legislated into a standard features. Lewis from Edmunds.com notes that a good family car will have glowing crash test scores and updates on safety technology including collision avoidance systems and blind-spot monitoring as options, if not standard features. But safety-focused Volvo has seen car sales slide 18.5% this year amid increasingly stringent safety standards that give competitors many of that safety-focused brand's key features. It's been a problem Volvo has faced for several years as Subaru (up 30%), Toyota (up 10%), Ford (up 3%) and others have expanded their safety features and met Volvo stride for stride. That Volvo's crossover sales have increased more than 23%, however, indicates that safety is still on families' minds, even if it's nearly ubiquitous.

“Safety is merely a cost of entry for automakers nowadays,” Allan says. “it’s getting harder and harder to find vehicles that fall far below their category’s average safety rating.”

— Written by Jason Notte in Portland, Ore., for MainStreet

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This article is commentary by an independent contributor. At the time of publication, the author held TK positions in the stocks mentioned.