1. A word used by children to frighten.

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

• boi,
• bv,
• yo,
• blo,
• bor,
• boc,
• bof,
• bf,
• ao,
• bok,
• bou,
• btoh,
• boh,
• bfor,
• bpo,
• eo,
• bu,
• bro,
• abou,
• bj

• boy,
• o,
• BOU,
• ba,
• br,
• bu.,
• bog,
• b.c.,
• by,
• box,
• boye,
• bob,
• Boyea,
• be-,
• bow,
• b.s.,
• be,
• b.a.,
• co,
• co-,
• o.,
• bi-,
• Boe,
• no,
• boa,
• bouie,
• BOWE,
• boo,
• no.,
• b's,
• B,
• co.,
• bowie.

The adjective form of the word "bo" is "boish," which means resembling or characteristic of a bo.

The plural of the "BO" can be the "bos".

The singular of the "BO" can be the "BO".