'Tower' in the Bible

Hear another parable: There was a householder who planted a vineyard, and made a fence round it, and dug a winepress in it, and built a tower, and let it out to husbandmen, and left the country.

And he began to say to them in parables, A man planted a vineyard, and made a fence round it and dug a wine-vat, and built a tower, and let it out to husbandmen, and left the country.

Or those eighteen on whom the tower in Siloam fell and killed them, think ye that they were debtors beyond all the men who dwell in Jerusalem?

For which of you, desirous of building a tower, does not first sit down and count the cost, if he have what is needed to complete it;