To ride or a messenger
Ryer is a rare surname-turned-given name likely derived from the Middle Dutch word 'ridere', meaning a rider or horseman. It can also be interpreted as a variation of the English occupational name Ryder, referring to a mounted messenger or forest ranger.
Less common today
Ryer isn't in the latest US Top 1000. It last peaked at #5,738 in 2008.
US births per 5-year period, 1990βpresent (SSA data).