mi·cro·fos·sil 
(mīkrō-fŏs′əl)
(mīkrō-fŏs′əl)n.
A fossil, as of a pollen grain or unicellular organism, that is too small to study with the naked eye.
- over-
- over a barrel
- overabundance
- overabundant
- overabundantly
- overachieve
- overachievement
- overachiever
- overact
- overaction
- overactive
- overactivity
- over against
- overage
- overage
- overaggressive
- overaggressively
- overall
- overambition
- overambitious
- overambitiously
- over and above
- over and over
- overanxiety
- overanxious