Mammoth Uncensored Word List:
40 words ending with as, 4 letters long

abas agas ahas aias alas baas bias boas bras caas ceas eras etas eyas faas goas hoas kaas keas koas kvas leas maas mnas nyas ocas odas okas peas pias poas pyas seas skas spas teas upas uvas yeas zeas