HighestOrder is the name of an optional argument. Its value is an integer, which gives an upper bound on to what order a solution of the deformation equation is lifted. Default value is 20.
The object HighestOrder is a symbol.
The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/VersalDeformations.m2:1820:0.