The letters in PORTABLE make 270 words of two letters or more. The longest is PORTABLE at 8 letters, and the highest-scoring is PORTABLE at 12 points.
No other single word uses all 8 letters of PORTABLE. PORTABLE has 8 letters: 3 vowels and 5 consonants, worth 12 points before any board bonuses.
8-letter words 1
7-letter words 6
bloater9potable11probate11prolate9retablo9ropable11
6-letter words 18
boatel8boater8bolter8borate8boreal8labret8lobate8oblate8palter8parole8patrol8pelota8petrol8plater8portal8protea8rebato8replot8
5-letter words 55
abler7abort7alert5alter5aport7apter7artel5baler7blare7blate7blear7bleat7bloat7boart7bolar7boral7botel7labor7later5leapt7lepta7lobar7loper7oater5opera7orate5paler7palet7pareo7parle7parol7pater7pearl7peart7petal7plate7pleat7polar7poler7prate7probe9prole7ratel5rebop9repot7roble7taber7table7tabor7taler5taper7tepal7tolar5toper7trope7
4-letter words 95
abet6able6aero4aloe4alto4aper6atop6bael6bale6bare6bate6bear6beat6belt6beta6blae6blat6blet6blot6boar6boat6bola6bole6bolt6bora6bore6bort6bota6brae6brat6earl4late4leap6lear4lept6lobe6lope6lore4lota4olea4opal6oral4orle4pale6pare6part6pate6peal6pear6peat6peba8pelt6pert6plat6plea6pleb8plot6poet6pole6pore6port6prao6prat6proa6rale4rapt6rate4rato4real4reap6repo6robe6role4rope6rota4rote4rotl4tael4tale4tape6tare4taro4tarp6teal4tear4tela4tepa6toea4tola4tole4tope6tora4tore4trap6trop6
3-letter words 74
abo5alb5ale3alp5alt3ape5apt5arb5are3art3ate3bal5bap7bar5bat5bel5bet5boa5bop7bot5bra5bro5ear3eat3era3ert3eta3lab5lap5lar3lat3lea3let3lob5lop5lot3oar3oat3obe5ole3ope5opt5ora3orb5ore3ort3pal5par5pat5pea5per5pet5poe5pol5pot5pro5rap5rat3reb5rep5ret3rob5roe3rot3tab5tae3tao3tap5tar3tea3tel3toe3top5tor3
2-letter words 21
ab4ae2al2ar2at2ba4be4bo4el2er2et2la2lo2oe2op4or2pa4pe4re2ta2to2
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.