1. Lowest.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• lowerst,
• lowerest,
• afermost,
• kowermost,
• powermost,
• oowermost,
• liwermost,
• lkwermost,
• llwermost,
• lpwermost,
• l0wermost,
• l9wermost,
• loqermost,
• loweremost,
• lowrmost,
• lowemost,
• lowermos,
• lowarmost,
• lowercost,
• Lownimist

• lowest,
• warmest,
• lamest,
• Lorenzo.

The adjective form of the word "lowermost" is "lowest".

The plural form of "lowermost" is "lowermosts".

The singular form of the word "lowermost" is "lowermost".