1. To write one's name at the foot or end of.

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

• indesign,
• understan,
• undersigner,
• underspin,
• undersatn,
• understen,
• underskin,
• understion,
• yndersign,
• hndersign,
• jndersign,
• indersign,
• 8ndersign,
• 7ndersign,
• ubdersign,
• umdersign,
• unsersign,
• undersighn,
• undesign,
• untersign

• underseller,
• underclass,
• underspent,
• underage,
• undergrow,
• underspend,
• underseal,
• undergarment,
• undersexed,
• underfur,
• understudy,
• undersize,
• underneath,
• underline,
• unaddressed,
• undergrad,
• understated,
• under wraps,
• underhanded,
• underpants,
• undershoot,
• underpin,
• underwear,
• underslung,
• undershirt,
• underpass,
• underground,
• undersell,
• underworld,
• underwater,
• understood,
• underdone,
• under fire,
• understand,
• undergird,
• undersea,
• underdown,
• undergrowth,
• underlying,
• undermine,
• undershot,
• undersized,
• underdress,
• undercover,
• undersoil,
• underskirt,
• underwriter,
• undermanned,
• underling,
• undertone,
• undercurrent,
• unadorned,
• undershrub,
• underdog,
• understate,
• undertaker,
• underwing,
• underhung,
• understock,
• underweight,
• underpart,
• untier,
• underhand,
• underdrawers,
• undersealed,
• under arms,
• undergo,
• underwrite,
• underside,
• underboss,
• underprice,
• underscore,
• undoer.

The adverb form of the word "undersign" is "undersignedly".

The adjective form of "undersign" is "undersigned".

The plural form of the word "undersign" is "undersigns".

The singular form of the word "undersign" is "undersigner".