Synonyms For "Supportive" :

2 syllables:

adjunct

3 syllables:

adjuvant, confirming, positive, supporting

4 syllables:

accessary, accessory, ancillary, appurtenant, auxiliary, collateral, confirmative, encouraging, validating, verifying

5 syllables:

confirmatory, corroborative, substantiating, substantiative, validatory

6 syllables:

certificatory, corroboratory, verificatory