Drill inmeaning

I guess that the speaker means repeat by drill there, but I am in doubt because the Oxford Dictionary, which appears to me the most compehensive, dosn't provide the definition.

Drill as a verb also appears in dictionaries, but with a different usage. Here, it used to mean that someone instructs someone else by means of a drill (a repeated exercise):

Drill inslang

Although a noun, I believe this is an example of a noun spontaneously being used as a verb. In the context of self teaching or self study, it means to perform a drill (a repeated exercise) on or about something:

Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

It is possible that the self-study sense of the verb drill (drilling multiplication tables, flashcard, and so on) was not common enough to warrant a separate dictionary entry.