Today's AWAD is "diriment":

diriment (DIR-uh-ment) adjective

Nullifying.

[From diriment-em, present participle of dirimere (to separate or interrupt), from emere (to take). Ultimately from Indo-European root em- (to take or distribute) that is also the source of words such as example, sample, assume, consume, prompt, ransom, vintage, and redeem.]

Merriment can be a diriment to success as we discover in today's ALAD.