'Tener' is the Spanish verb 'to have.' As well as using it to signify possession i.e. 'I have a brother', you can also use this verb to form some expressions which are in the Tango'r Tengo song. In English, we use a form of the verb 'to be' (am, is, are, was, were, etc.) and an adjective (hungry, thirsty, sleepy, etc.) for these expressions. In Spanish, however, we do not use 'ser' or 'estar' and an adjective; we use the verb 'tener' and a noun for all of these expressions. In other words, in Spanish, you are not hungry, you have hunger.