Definify.com
Webster 1913 Edition
Semi-
Sem′i-
.[L.
semi
; akin to Gr. [GREEK][GREEK][GREEK], Skr. sāmi
-, AS. sām
-, and prob. to E. same
, from the division into two parts of the same size. Cf. Hemi-
, Sandelend
.] A prefix signifying half, and sometimes partly or imperfectly;
as,
. semi
annual, half yearly; semi
transparent, imperfectly transparent☞ The prefix semi is joined to another word either with the hyphen or without it. In this book the hyphen is omitted except before a capital letter; as, semiacid, semiaquatic, semi-Arian, semiaxis, semicalcareous.