5
reinforcement(noun, support, stay, bar, prop)
4
advocate(verb, support, help, develop, cause)
4
beam(noun, shaft, pole, timber, strut)
4
bear up(verb, expression, phrasal verb, hold, help)
4
bedding
4
blow up(verb, expression, phrasal verb, increase, open)
4
cheer(verb, support, hold, help, maintain)
4
comfort(verb, support, hold, help, keep)
4
expand(verb, increase, open, develop, extend)
4
fill out(verb, expression, phrasal verb, increase, open)
4
further(verb, support, take, help, advance)
4
long pillow(noun, expression, idiom)
4
nurture(verb, support, help, give, advance)
4
shore(noun, verb, support, hold, set)
4
substantiate(verb, support, hold, help, increase)
4
undergird(verb, hold, maintain, uphold, reinforce)
3
aggrandise
3
augment(verb, support, increase, open, develop)
3
bear out(verb, expression, phrasal verb, hold, help)
3
beef up(verb, expression, support, increase, open)
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APASmart Define. (2016). bolster thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/bolster/thesaurus/synonyms
ChicagoSmart Define. 2016. "bolster thesaurus" https://smartdefine.org/bolster/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2016, bolster thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/bolster/thesaurus/synonyms>.
MLASmart Define. "bolster thesaurus" 26 February 2016. Web. 26 September 2026. <https://smartdefine.org/bolster/thesaurus/synonyms>