View source for Imbedded word

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''occurrence''

A [[Word|word]] of a special type containing complete information about the position of one word inside another. More precisely, an occurrence in an [[Alphabet|alphabet]]  $  A $
is a word of the form  $  P \star Q \star R $, 
where  $  P, Q, R $
are words in  $  A $, 
while  $  \star $
is not a letter of that alphabet. The occurrence  $  P \star Q \star R $
is also an occurrence of the word  $  Q $
into the word  $  PQR $. 
The word  $  Q $
is called the base of this occurrence; the words  $  P $
and  $  R $
are known as the left and right wings, respectively. The concept of an occurrence may be made the base of a system of concepts which is convenient for the study of the syntactic structure of words of one type or another.

====References====
<table><TR><TD valign="top">[1]</TD> <TD valign="top">  A.A. Markov,   "Theory of algorithms" , Israel Program Sci. Transl.  (1961)  (Translated from Russian)  (Also: Trudy Mat. Inst. Steklov. 42 (1954))</TD></TR><TR><TD valign="top">[2]</TD> <TD valign="top">  N.M. Nagornyi,   "The theory of algorithms" , Kluwer  (1988)  (Translated from Russian)</TD></TR></table>

====Comments====
The phrase  "imbedded word"  is not in common use in English. The (English) translation [[#References|[1]]] speaks of an entry of one word in another and of left and right delimiters (rather than occurrence, left and right wings, which are used in the (English) translation [[#References|[2]]]). Other English-speaking authors tend to refer to an occurrence of one word as a subword (or segment) of another.

====References====
<table><TR><TD valign="top">[a1]</TD> <TD valign="top">  S. Eilenberg,   "Automata, languages and machines" , '''A''' , Acad. Press  (1974)</TD></TR><TR><TD valign="top">[a2]</TD> <TD valign="top">  J.L. Britton,   "The word problem"  ''Ann. of Math.'' , '''77'''  (1963)  pp. 16–32</TD></TR></table>