1) Straight line 
An adjective meaning 'of a probability distribution as some variable or parameter of it (usually, the size of the sample from another distribution) goes to infinity.' In particular, see asymptotic distribution. Contexts: econometrics
Pertaining to a limiting value, for example of a dependent variable, when the independent variable approaches zero or infinity. ... (05 Mar 2000) ... 
Type: Term Pronunciation: ā′simp-tot′ik Definitions: 1. Pertaining to a limiting value, for example of a dependent variable, when the independent variable approaches zero or infinity.
[adj] - relating to or of the nature of an asymptote
asymptotic, asymptotical 1. Referring to an asymptote. 2. Approaching a given value as an expression containing a variable tends to infinity. 3. Of two functions, so defined that their ratio approaches unity as the independent variable approaches a limit or infinity. 4. With reference to a formula, becoming increasingly exact as a variable approa...
adjective relating to or of the nature of an asymptote; `an asymptotic function`
of or pertaining to an asymptote. · (of a function) approaching a given value as an expression containing a variable tends to infinity. · (of two functions) so defined that their ratio approaches unity as the independent variable approaches a limit or infinity. · (of a formula) becoming increasingly exact as a variable approaches ...