Pronunciation: (sī), [key]
a male given name, form of Seymour, Simon, or Silas.
var. of syn- before s followed by a consonant and before z: systaltic; syzygy.
a suffix forming nouns or adjectives, sometimes a diminutive of the base word and usually confined to informal and jocular use (bitsy; footsie; halvsies); adjectives formed with -sy may be ironic, implying that the quality in question is self-consciously assumed or feigned (artsy; cutesy; folksy). The combination of -s 3 and -y 1 or -y 2 in certain words (antsy; gutsy) should perhaps be considered further instances of this suffix.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.