substantial vs significant

substantial and significant both are adjectives.

Word	Noun	Adjective	Verb	Adverb
substantial	No	Yes	No	No
significant	No	Yes	No	No

As adjectives, substantial and significant are synonyms defined as:

substantial (adjective)	significant (adjective)
having substance or capable of being treated as fact; not imaginary	important in effect or meaning
of considerable importance, size, or worth	too closely correlated to be attributed to chance and therefore indicating a systematic relation
of or relating to the real nature or essential elements of something	of considerable importance, size, or worth
having an abundant supply of money or possessions of value	rich in significance or implication
of good quality and condition; solidly built
providing abundant nourishment