The letters in PROPOSAL make 111 words of two letters or more. The longest is PROPOSAL at 8 letters, and the highest-scoring is PROPOSAL at 12 points.
No other single word uses all 8 letters of PROPOSAL. PROPOSAL has 8 letters: 3 vowels and 5 consonants, worth 12 points before any board bonuses.
8-letter words 1
7-letter words 2
apropos11poplars11
6-letter words 6
orlops8parols8polars8poplar10saloop8sporal8
5-letter words 21
loops7opals7orals5orlop7palps9parol7plops9polar7polos7pools7poops9praos7proas7props9proso7sapor7sloop7solar5sopor7spool7spoor7
4-letter words 39
alps6also4apps8laps6lars4loop6loos4lops6oars4oops6opal6oral4osar4palp8pals6paps8pars6plop8polo6pols6pool6poor6poos6pops8prao6proa6prop8pros6raps6rasp6salp6slap6slop6soap6soar4sola4solo4sora4spar6
3-letter words 28
alp5als3ars3asp5lap5lar3las3loo3lop5oar3ops5ora3ors3pal5pap7par5pas5pol5pop7pro5rap5ras3roo3sal3sap5sol3sop5spa5
2-letter words 14
al2ar2as2la2lo2ls2oo2op4or2os2pa4ps4rs2so2
Words are from our open word list and include some game-only words. Rude words are left out of this page; the unscrambler shows every valid word, lets you add blank tiles and filter by length.