Rabbits are considered not to be so vocal and they often use their body language to pass most of their messages. They may use their body language to show various sentiments such as excitement, pain, sexual desires, fear and so on.
Meaning of honking or rabbit buzzing
If your bunny has been oinking lately, you need to consider various circumstances before concluding on the meaning of this sound.
Here is how ‘honking sounds like’
Here is a video to let you know when your rabbit is honking to be able to differentiate this sound from other sounds that rabbits use to talk.
This sound is not only made by adult bunnies by may also be used by kits to communicate to their mother. Here are common reasons why these pets honk.
As a courting sound
Soft honking may be a courting rabbit sound. Both intact male and female rabbits may oink when they are on heat. However, unneutered males are known to make this sound more often than females.
For instance, a doe softly and melodiously honking may mean 'come-hither' or 'not tonight, dear'. 
When oinking is a courting sound, it may be accompanied by other courting behaviors including circling another rabbit or your leg and mounting. However, circling may also mean that your furry critter needs your attention, food, or a fight is about to erupt.
A sign of excitement
Besides courting, it could also be a sign of eagerness and excitement, especially in neutered and sprayed rabbits. You will notice the honking when you are about to feed them with their favorite treat, when you pet it (stroke), or they may do it while chasing each other. This is trying to say, ‘I am excited’, ‘I am happy’, or ‘I am contented’
Oinking is one of the affectionate, happy or excited rabbit sounds together with others such as purring, clucking and humming. It can also be accompanied by body language such as flopping, running, leaping, or dancing. 
To get attention
Finally, this sound might be a way for these pets to ask you to give them attention. If you notice your bunny sited near you and honking, it may not be showing excitement or making a courting sound but rather asking for your attention.
Since bunnies may have slightly different ways of communicating, you need to consider the circumstance before drawing a conclusion.