The word “substantially” is a relative term and should be interpreted in accordance with the context of claim in which it is used. Moss v. Patterson Ballagh Corp. D.C.Cal., 80 P.Supp. C10, 637.
Meaning of substantial depends on context
Words & Phrases 64 (p.759)
“Substantial” is a relative term, the meaning of which is to be gauged by all the circumstances surrounding the transaction, in reference to which the expression has been used. It imports a considerable amount or value in opposition to that which is inconsequential or small.