Correct Terminology for "Smallest" Number which could be Negative

Question

I'm writing a paper and I'm doubting myself with a piece of terminology.

I am finding roots of an equation, say {x1, x2}, where it's ambiguous which is greatest from the parameters involved. So possibly x1>x2 or x2>x1.

What is the correct term for the one of these which is the closest to $-\infty$?

I'm tempted to use the word "small", but to me that suggests closest to $0$. I also can't use "most negative" as there's a chance they're both positive.

Suggestions appreciated

Answer 1

As @Berci says, least would likely be a good option here. It carries neither the "closest to zero" connotation that small does, nor the "very positive" connotation that large does.

Edit:

@Logophobic's suggestion of "minimum" is also relevant, and between the two I think completely answers the question.