insufficiently
adv. degree B2 Upper Intermediate US //ˌɪnsəˈfɪʃəntɫi// UK //ɪnsəfˈɪʃəntli// in·suf·fi·cient·ly
adv. not enough for what is needed. You use this to describe something that is too small, too short, or not good enough to do the job.
adv. to a degree that is not enough for a particular purpose or requirement. Often used to modify adjectives or verbs to indicate a lack of adequacy.
The evidence is insufficiently strong to prove the case.
The bridge was built insufficiently to handle the weight of modern trucks, leading to its closure for repairs.
While the initial data suggested a correlation, the researchers noted that the sample size was insufficiently large to draw any definitive conclusions about the population as a whole.
From insufficient + -ly or in- + sufficiently.