1. Not to be obtained.

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

• unnatainable,
• unstainable,
• unoptainable,
• unattianable,
• unattanable,
• unatainable,
• unattinable,
• unattaibable,
• untainable,
• unabtainable,
• unattaiable,
• unatanable,
• untrainable,
• unatainble,
• unotainable,
• unnattainable,
• unattakable,
• unattackible,
• unattainabel,
• unatteinable

• unattainably,
• unthinkable,
• untenable,
• unthankful,
• unthinkably,
• unattended.

The adjective form of "unattainable" is "unattainable".

The plural form of "unattainable" does not change. It remains the same.

The singular form of the word "unattainable" is "unattainable".