Abarim Publications' online Biblical Hebrew Dictionary
Scholars have identified two separate roots זוז (zwz), but some scholars (the brilliant Gesenius for instance) have proposed that they're really one and the same. Others refute this; BDB calls it very dubious. Still, even though these two roots may be linguistically separated, they are still similar, and the poets who used them will not have left that characteristic idle:
The unused root זוז (zwz I) occurs in cognate languages where it means something like to move or rise, come forth or be agitated. In the Hebrew of the Bible only two derivatives remain, which strongly suggest that our verb emphasizes a cyclic movement, like ebb and flow:
- The masculine noun זיז (ziz), denoting moving things (like wild animals) collectively (Psalm 50:11 and 80:13).
- The feminine noun מזוזה (mezuza), meaning door- or gate-post. HAW Theological Wordbook of the Old Testament, oddly enough, declares this noun's relation to the root uncertain, and perhaps this is so in a strictly linguistic way. Practically, door-posts are quite obviously the items in which door blades move (the letter mem in front of the root denotes a "place of" motion). This noun is also the source of the familiar word Mezuzah, the small container holding a mini-scroll that reads Deuteronomy 6:4-9 and 11:13-21. This Mezuzah is traditionally attached to the outside right doorpost of a house.
The also unused root זוז (zwz II) is proposed to mean to be abundant. Its only derivative זיז (ziz, which is remarkably similar to the one treated above, denoting moving things) occurs only in Isaiah 66:11, where the prophet possibly speaks of the "abundance" of glory. But on the other hand, he might actually employ a state of motion to indicate the health of the said glory. Hebrew is a dynamic language; things are defined after their behavior, and nouns are usually derived from verbs; English is a static language where things are known for what they look like and verbs usually come from nouns (see our explanatory article To Be Is To Do).