From sub- + potent. <span class="searchmatch">subpotent</span> (comparative more <span class="searchmatch">subpotent</span>, superlative most <span class="searchmatch">subpotent</span>) Less than potent; not potent enough. a <span class="searchmatch">subpotent</span> drug...
From sub- + potency. subpotency (countable and uncountable, plural subpotencies) The quality of being <span class="searchmatch">subpotent</span>....