sis

play
noun \ˈsis\

Definition of sis

  1. :  sister —usually used in direct address

1656

First Known Use of sis

1656


SIS

abbreviation

Definition of SIS

  1. Secret Intelligence Service The Secret Intelligence Service is a British government agency that is responsible for the collection and analysis of information about foreign countries or groups.


-sis

noun suffix

Definition of -sis

plural

-ses

  1. :  process :  action peristalsis

Origin and Etymology of -sis

Latin, from Greek, feminine suffix of action

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