1. Not able; not having sufficient ability or means; weak; not having adequate knowledge or skill.

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

• unables,
• unbable,
• unabkle,
• anamle,
• unckle,
• unavable,
• anazle,
• usuable,
• aunble,
• anoble,
• unalb,
• ennable,
• unsable,
• enablle,
• eable,
• unalble,
• unabel,
• uinable,
• anabled,
• unccle

• unblessed,
• unvalued,
• unbolted,
• unveiled,
• unpleated,
• unbolt,
• unfiled,
• unfelled,
• unfledged,
• unbelief,
• unfilled,
• unblended,
• unfueled,
• unbalance,
• unbelt,
• univalent,
• unpledged,
• unbeloved,
• unfailing,
• unbelted.

The adjective form of "unable" is "incapable".

The plural form of the word "unable" is "unables".

The singular form of the word "unable" is "unabled"