is scale a melody?part I

Let us ,firstly, define what a scale is. A row of ascending or descending notes.But how many notes in a row is enough to form a scale?There are scales containing 5, 6,7 or even 11 different notes.

In common practice a scale is mistaken with music tone material. Isn’t it? Maybe a way of defining what a scale is, would be that we are actually only playing music material from a certain key center going from a certain point and in ascending or descending manner ending on the same note one octave higher or lower.