In the Hebrew Bible, there are a number of other words that, like "Nephilim", are sometimes translated as "giants":
Emim — the fearful ones
Rephaim — the dead ones
Anakim — the [long]-necked ones
Anakim (or Anakites) are the descendants of Anak, and dwelt in the south of Canaan, in the neighbourhood of Hebron. In the days of Abraham, they inhabited the region later known as Edom and Moab, east of the Jordan river. They are mentioned during the report of the spies about the inhabitants of the land of Canaan. The Book of Joshua states that Joshua finally expelled them from the land, excepting a remnant that found a refuge in the cities of Gaza, Gath, and Ashdod. The Philistine giant Goliath, whom David[42] later encountered, was supposedly a descendant of the Anakim.[citation needed]
The land, through which we have gone to spy it out, is a land that devours its inhabitants, and all the people that we saw in it are of great height. And there we saw the Nephilim (the sons of Anak, who come from the Nephilim), and we seemed to ourselves like grasshoppers, and so we seemed to them.
—Numbers 13:32–33, English Standard Version
http://en.wikipedia.org/wiki/Anakim#Related_terms
Emim
From Wikipedia, the free encyclopedia
The Emim ([pronunciation?]; Hebrew: אֵמִים) was the Moabite name for one of the tribes of Rephaim. They are described in Deuteronomy chapter 2 as having been a powerful people, populous and having a successful kingdom. They were defeated by the Moabites, who occupied their land. The Emim are also mentioned in Genesis 14:5 and according to Rashi,
the name is translated as "the dreaded ones" (Hertz 1936) and the singular Ema/Emma (Hebrew: אימה) means "horror" or "terror".
"The Emims dwelt therein in times past, a people great, and many, and tall, as the Anakim" (Deuteronomy 2:10-11).
http://en.wikipedia.org/wiki/Emim