• aix-footer,
• zix-footer,
• xix-footer,
• dix-footer,
• eix-footer,
• wix-footer,
• sux-footer,
• sjx-footer,
• skx-footer,
• sox-footer,
• s9x-footer,
• s8x-footer,
• siz-footer,
• sic-footer,
• sid-footer,
• sis-footer,
• six0footer,
• sixpfooter,
• six-dooter,
• six-cooter

The adjective form of the word "six-footer" is "six-foot".

The plural form of the word "six-footer" is "six-footers".

The singular form of the word "six-footer" is "six-footer" itself. Since "six-footer" is a noun that refers to a person who is six feet tall, it remains the same in both singular and plural forms.