IPA: /səbˈstæn.tɪ.və.li/
KK: /səb'stæn.tɪv.ə.li/
In a way that relates to a noun or a substantive; in a manner that emphasizes the essence or substance of something.
The changes were substantivally significant to the overall project.
Substantivally → It is formed from "substantivus" (from Latin, meaning substantial or having substance) and the suffix "-ally" (meaning in a manner of). The word "substantivally" means in a manner relating to or characteristic of a substance or noun.
Think of 'substance' to remember that 'substantivally' refers to something done in a manner related to substance or nouns.