1. Lasting through a year
   "attending yearlong courses"

See also: long

• underwriter
• undescended
• undescended testicle
• undescended testis
• undescriptive
• undeserved
• undeservedly
• undeserving
• undesigned
• undesirability
• undesirable
• undesirably
• undesired
• undesiring
• undesirous
• undestroyable
• undetectable
• undetected
• undeterminable
• undetermined
• undeterred
• undeveloped
• undeviating
• undiagnosable
• undiagnosed