The meaning of GIVEN

the meaning of GIVEN

The passage below is from ‘the Blank Slate’ by Steven Pinker.

http://evolbiol.ru/blankslate/blankslate.htm


In Words and Rules I aimed a microscope on a single phenomenon of language that has served as a test case for the ability of generic associative networks to account for the essence of language: assembling words, or pieces of words, into new combinations. People don't just memorize snatches of language but create new ones. A simple example is the English past tense. Given a neologism like to spam or to snarf, people don't have to run to the dictionary to look up their past-tense forms; they instinctively know that they are spammed and snarfed.

In this passage I want to know what the underlined Given means.

In the Cobuild dictionary, I found the meanings probably fit to the context in question.

http://dictionary.reverso.net/english-cobuild/given
?given
3 prep Given is used when indicating a possible situation in which someone has the opportunity or ability to do something. For example, given the chance means `if I had the chance'.
? Write down the sort of thing you would like to do, given the opportunity.
? Given patience, successful breeding of this species can be achieved.
4 phrase If you say given that something is the case, you mean taking that fact into account. (=considering)
? Usually, I am sensible with money, as I have to be, given that I don't earn that much.

But between these two meanings, I cannot decide which best fits to the sentence in question.
(I think #3 is the better answer, though.)
Help me.

Regards.