underwhelm (verb) - to fail to impress, interest, or excite; to disappoint [uhn-der-hwelm]
overwhelm (verb) - to overpower in thought, feeling, or superior force; to bury, inundate, or defeat [oh-ver-hwelm]
BREAKDOWN: The word underwhelm is a relatively new addition to the English language, first coined in the mid-20th century. Overwhelm is much older. Both words are based on the Old English hwielfan (Middle English whelmen ) meaning to cover over, overthrow, or submerge completely. While whelm used to be used synonymously with overwhelm, nobody seems to be whelmed anymore.
“Your wit never ceases to underwhelm me.” —A.E. Kirk
[Our Wednesday Wildcards are fascinating and important words that are not necessarily derived from classical roots.]