Zero
zeroZero.
Zillion, Zipf's Law, Zoomeron Equation, z-intercept, z-axis
zero
The only one I can think of is zero.
A five (5) letter word that starts with Z and ends with F, there is none recorded. However, there is a word that starts with Z and ends with F. The word is a four (4) letter word: zarf, (noun) a metal holder for a coffee cup.
Zealous is a positive word. It starts with the letter z.
5 letter words that start with Z: zealot
Zeal
Zebra
zoozitzipzapzen
Zoology
· Zinnia