forming words, with the meanings:
under, beneath, or below
subsoil
submarine
next in rank below; subordinate
subdeacon
a subordinate portion or subdivision of something
subcommittee
a repeated or further instance of a specified action or process
subcontract
sublet
bearing an incomplete, partial, or inferior resemblance to; approximately
subhuman
adjacent to or bordering on
subarctic
said of a chemical compound: containing less than the normal or usual amount of a specified element
suboxide
[Middle English from Latin sub- under, below, secretly, from below, up, near, from sub under, close to, during]