understandable, a. comprehensible, intelligible.
understanding, n. [comprehension], [discernment], [apprehension]; [accord], entente, [harmony], [agreement]. Associated word: tacit.
under the rose. secretly, privately, confidentially, sub rosa.
undervalue, v. depreciate, vilipend, [despise]; [underrate], underestimate.
under water. submarine, subaquatic, subaqueous, submerged.
underwear, n. underclothing; lingerie.
underwrite, v. [insure]; subscribe.
undeserved, a. unmerited, [unjust].
undeserving, a. [unworthy], unmeritorious, indign.
undesigned, a. [unpremeditated], [unintentional], [accidental].