Definition of straight-line
1
: being a mechanical linkage or equivalent device designed to produce or copy motion in a straight line
2
: having the principal parts arranged in a straight line
3
: marked by a uniform spread and especially in equal segments over a given term
- straight-line amortization
- straight-line depreciation
4
: occurring, measured, or made in or along a straight line
- straight-line motion
- straight-line extrapolation
