epsilon
[see delta] 1. n. A small quantity
of anything. "The cost is epsilon." 2. adj. Very small,
negligible; less than marginal.
"We can get this feature for epsilon cost." 3. `within epsilon
of': close enough to be indistinguishable for all practical
purposes, even closer than being `within delta of'. "That's not
what I asked for, but it's within epsilon of what I wanted."
Alternatively, it may mean not close enough, but very little is
required to get it there: "My program is within epsilon of
working."