IPA: /nɒnˈaɪdəl/
KK: /nɑnˈaɪdəl/
Not the best or most suitable; not meeting the ideal standard.
The nonideal conditions made it difficult to complete the experiment successfully.
Comparative: more nonideal
Superlative: most nonideal
Nonideal → It is formed from "non-" (meaning not) and "ideal" (from Greek "idealis", meaning pertaining to an idea or standard of perfection). The word "nonideal" means not conforming to an ideal or standard of perfection.
Think of 'non-' meaning 'not' and 'ideal' referring to a standard of perfection — so nonideal describes something that does not meet that perfect standard.