Judas -- "Judas" is from the Hebrew name "Judah" in Greek letters. The "s" comes from the Latin when the word is a subject.

thou -- This is from the second-person, singular form of the verb. This helping verb indicates the present tense of the verb. It is used here to form the present, progressive tense, which doesn't exist in Greek but which can smooth the flow of English sentences.

thou -- This is from the second-person, singular form of the verb.

betraying -- (CW, WF) "Betrayest thou" is a compound word that literally means "to give over". It is often translated in the KJV as "betray" but it has no historical sense of denouncing someone, though it may have acquired that sense from the Gospels. Its meaning is the idea of transmitting, and handing over. It can even be used in a positive sense, such as "bestowing" a gift. Though in this context, the sense is probably "handing one" over to authorities. This word doesn't precisely mean "betray". This is not a participle, "betraying", but an active verb. 

The phrase "the son of man" is the common way Jesus refers to himself. It is discussed in detail in this article. 

the -- The word translated as "the" is the Greek definite article. The Greek article is much closer to our demonstrative pronouns ("this", "that", "these", "those"). See this article for more. 

Son -- The word translated as "son" more generally means "child" or "descendant." The phrase "the son of man" is the common way Christ refers to himself. It is discussed in detail in this article. Its sense may be "the child of the man".

of -- This word "of" comes from the genitive case of the following word that required the addition of a preposition in English.  The most common is the "of" of possession, but it can also mean "belonging to", "part of", "which is", "than" (in comparisons), or "for", "concerning" or "about", with transitive verbs. 

missing "the"  -- (MW) The untranslated word is the Greek definite article, which usually precedes a noun and, without a noun, takes the meaning of "the one". The Greek article is much closer to our demonstrative pronouns ("this", "that", "these", "those"). See this article for more. 

man - The Greek word for "man" means "man", "person" and "humanity" in the singular. In the plural, it means "men", "people" and "peoples". 

with-- This word "with" comes from the indirect object form of the following word that requires the addition of a preposition in English. The most common is a "to" for the English indirect object. However, the translator can choose other prepositions: "with", "in", "of", "as", "by", "for", "at" or "on" depending on the context.

a -- There is no indefinite article in Greek, but when a noun doesn't have a definite article, the indefinite article can be added in English translation.

kiss -- The word translated as "with a kiss" means "kiss". It is a noun with the same root as one of the verbs often translated as "love". See this article.