Snoring is categorised as a coarse noise made by vibrations of the soft palate and other tissue in the mouth, nose & throat. For the purposes of getting a good night's sleep snoring can be very bad news for your partner.
There are many different kinds of snoring or snorer depending on where the vibrations come from - the nose, throat or soft palate, or some combination. Sleep apnoea is a more serious condition where the blockage can cause oxygen deprivation.
Snoring is caused by turbulence inside the airway whilst breathing in. The turbulence is caused by a partial blockage that may be located anywhere from the tip of the nose to the vocal chords. The restriction is more likely to occur during sleep because our muscle tone is reduced and there may be insufficient muscle tone to prevent the airway tissue vibrating. During waking hours muscle tone keeps the airway in good shape; that's why we don't tend to snore when awake.
The fact that there are many different types of snore means that to manage the condition requires a tailored solution. It is more about managing the condition rather than curing it though.
This website here is very informative british snoring and sleep apnoea association It offers some solutions and a way to tell what kind of snorer you are.
Alternatively it may just be a matter of investing in some good earplugs for your partner. Here's the new range from The Snoozery. Handy Bags of Earplugs