Deficient (adjective)

1. Lacking or insufficient in some respect or quality.
2. Not meeting a necessary standard or requirement.

Origin:

Derived from the latin word 'deficere' meaning 'to fail'.

Examples:

1. The deficient rainfall has caused a severe drought in the region.
2. The deficient performance of the team led to their elimination from the tournament.
3. The deficient security measures led to a breach in the system.
4. The deficient supply of food caused widespread hunger.
5. The deficient lighting made it difficult to see the stage during the performance.