In terms of polarity, aldehydes and ketones are best described as which?

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Polarity in aldehydes and ketones comes from the carbonyl group. The C=O bond has a noticeable electronegativity difference between carbon and oxygen, so oxygen pulls electron density toward itself. This creates a partial negative charge on oxygen and a partial positive charge on the carbon, giving the molecule a dipole moment. That polar carbonyl is the dominant feature, even though there may be nonpolar carbon chains attached; the overall molecule behaves as polar because of that strong C=O bond and its ability to engage in dipole–dipole interactions and hydrogen-bond accepting behavior with water.

It's not ionic, since there are no full charges to form ions, and it's not nonpolar because the polar carbonyl bond imparts significant polarity. It's not amphipathic in the sense of having a distinct hydrophilic and hydrophobic region arranged like a surfactant, even though parts of the molecule can be nonpolar. So, aldehydes and ketones are best described as polar.