Below the best possible standard or level; not achieving the most favorable or ideal outcome. It describes performance or conditions that could be improved or are less than perfect.
From Latin 'sub' (under, below) + 'optimus' (best), forming a modern compound. 'Optimus' is the superlative of 'bonus' (good), so suboptimal literally means 'below the best.'
The word 'optimus' gives us 'optimism' and 'optimize,' but also the name 'Optimus Prime'! So suboptimal literally means 'below Prime quality' - not quite worthy of leading the Autobots!
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