Use of 'audience' for a single person

Can I say 'He was my audience', or 'He was the audience' if I ended up presenting to only one person in a meeting?

One can use the word audience for one person alone, but only if the nature of the event is such that there could have been, and normally would have been, more people attending it, and it just happened that nobody else showed up on the particular occasion. For example, suppose that a public lecture was announced, only one person came to attend it, and the lecture nevertheless went ahead in front of that one person sitting alone in the lecture hall. It could then be said that there was only one person in the audience; that would be perfectly correct, literal use of the word audience. The word would, however, not be used when speaking of the communications that are by their nature directed at one person only.

The phrase audience of one is more often used metaphorically, in the cases in which, even though there are many people in the audience in the literal sense, the opinion of only one among them really matters, and everything is therefore geared towards having a certain effect on that person. Religious people sometimes narrow this metaphorical sense to a more specific metaphor: they say that in living one's life one is performing for the audience of one, to convey that idea that it is only God's opinion of one's life that ultimately matters.

If one is considering using the phrase audience of one literally, one needs to be mindful of the prevalence of its metaphorical uses.