undersize is a valid English word

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

Meanings

Adjective (COMPARABLE)

Smaller than normal, undersized.
• This isn't a pony, it's just an undersize horse.
Smaller than appropriate, expected or sufficient.
Small enough to fit through a screen.

undersize is a Scrabble valid word

u1n1d2e1r1s1i1z10e1

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

undersize is not an iScramble, QuickWords valid word

u1n2d3e4r5s6i7z8e9

• The word is not valid in iScramble ✘
• The word is not valid in QuickWords ✘
• 45 points

Same letters words (Anagrams)

• UNRESIZED

Same letters plus one

• DOUZENIERS
• GERUNDIZES
• UNDERSIZED

Same letters minus one

• RESENDIZ
• SEIZURED
• UNDESIRE
• UNSEIZED