however is a valid English word

Scrabble validity: valid ( international - Sowpods, US - Twl06 )
iScramble validity: valid
QuickWords validity: valid

Meanings

Adverb (NOT COMPARABLE)

(conjunctive) Nevertheless; yet, still; in spite of that.
• He told me not to do it. However, I did it anyway. / I did it anyway, however. / I, however, did it anyway.
(conjunctive) In contrast.
• The conference itself went very well. The party afterwards, however, was a disaster.
(degree) To whatever degree or extent.
• However clear you think you've been, many questions will remain.

Conjunction

Regardless of the way in which.
• Let me know when you've had your interview, however it goes.
In any way in which.
• She offered to help however she could.
(proscribed) But, yet, though, although.
• *She wanted to go, however she decided against it. (proscribed)

however is a Scrabble valid word

however

• International English (Sowpods) - The word is valid in Scrabble ✔
• US English (TWL06) - The word is valid in Scrabble ✔
• 00 points

however is an iScramble, QuickWords valid word

however

• The word is valid in iScramble ✔
• The word is valid in QuickWords ✔
• 00 points

Same letters words (Anagrams)

• EVERWHO
• WHOEVER

Same letters plus one

• EVERYHOW
• HOWSEVER
• OVERCHEW
• WHOMEVER
• WHOSEVER

Same letters minus one

• REWOVE