“Milf” is not a legitimate word, at least in Words with Friends, but the letters “sh” do form a valid word. Such is the arcana of the popular Words with Friends game. Somebody, probably one of my daughters, downloaded this game with the result that I spend about an hour a day fiddling around with the ubiquitous yellow tiles. One of Apple’s most downloaded free apps, Words with Friends has become, for many, an addiction; there are even support groups and Facebook pages for those in need.
It is a struggle sometimes to play off the double and triple word squares, but there is satisfaction in scoring twenty or thirty points a play. There are, however, reports of single-play scores in the eighty point range and game scores well over 1000! BuzzFeed. These may be suspect because of possible collusion among “friends” or a contrived game by one person using two accounts.
For many, the attraction lies in dragging forth long-forgotten words. For example, I learned in college meteorology that “foehn” describes a hot southerly wind on the northern slopes of the Alps. “Foehn” is valid in Words, but it gets underlined in squiggly red in Word 97-2003, as do many other valid Words. “Heptose” was, I believe, taught in some long ago biochem class, and uses a 4-point "h".
The Z, J, and Q tiles present learning opportunities, and here the Words word checker tool can be handy. A "Q" (and there is only one in Words) with no "U" can be a challenge, but one could form quai, qat, or qi, all valid in Words (the anagram of qi, however, is not valid as an acronym).
J words commonly used when I play (i.e., jam, jerk, jet) tend to isolate a part of the board to further play; but one could expand things by playing jape (to speak mockingly), jehu (a wild coach driver), or hadj (Muslim pilgrimage). “Jazz” is out because there’s only one “Z” (although the word checker says it's valid), but zen, raze, azure, and blaze are all jake, which is itself a valid word, as is "hinky" which consumes a valuable 5-point "k".
An unofficial but helpful website can be found at Words with Friends