-er vs -ster

-er

suffix
  • Person or thing connected with. 

  • A thing that is related in some way to the root, such as by location or purpose. 

  • Used to form diminutives. 

  • Used to form slang or colloquial equivalents of words. 

  • A person or thing to which the root verb is done or can be done satisfactorily. 

  • Used to form nouns shorter than more formal synonyms. 

  • A person or thing that does an action indicated by the root verb; used to form an agent noun. 

  • More; used to form the comparative. 

  • Suffix denoting residency in or around a place, district, area, or region. 

  • A person who is associated with, or supports a particular theory, doctrine, or political movement. 

  • A suffix creating adjectives from verbs, indicating aptitude, proneness, or tendency toward a specified action 

  • Junior, child, younger person. (Attached to a name, usually a portion of the given name.) 

  • Suffix denoting a resident or inhabitant of (the place denoted by the proper noun); used to form a demonym. 

  • Frequently; used to form frequentative verbs. 

  • Instance of (the verbal action); used to form nouns from verbs. 

  • A person whose occupation is the root noun; (more broadly, occasionally with adjectives) a person characterized by the root. 

  • A person or thing to which a certain number or measurement applies. 

-ster

suffix
  • Someone who is, or who is associated with, or who does something specified. 

  • A diminutive appended to a person's name. 

How often have the words -er and -ster occurred in a corpus of books? (source: Google Ngram Viewer )