I have a lot to learn about Russian verb usage and structure, but at least I've been introduced and somewhat understand the difference between the perfective and imperfective aspect of a verb. Early on, I came across something that encouraged learning each imperfective aspect of a verb along with its perfective counterpart, saw the good sense in that, and have been trying to apply that advice ever since. Because of this, I had thought that every verb in the Russian language had an imperfective and perfective pairing.
That all changed today when I went to look up the word "значить." Having been one of the first words I learned in Russian, I've never bothered to look it up, but when I looked it up in Wiktionary today, I noticed that Wiktionary, which is usually pretty thorough, did not provide any perfective counterpart for this verb. Does this mean it doesn't have one? And if so, are there many verbs in Russian that don't have an aspectual pairing? In other words do many verbs in Russian have just an imperfective aspect or perfective aspect, but not both? Is there a list somewhere?