You are apparently looking for word search with case-sensitivity.
For case-sensitive search, set case-fold-search
to nil
.
You can also just toggle case-sensitivity temporarily, during Isearch, using M-c
.
For incremental word search, use M-s w
. For nonincremental word search, use M-s w RET
.
There are additional ways to do word search. See the Emacs manual, node Word Search.
Strike that, for you apparently do not want to find abcDEF
when it follows .
. So you want something different from word search.
In that case, use regexp search, looking for whitespace followed by word-constituent characters, e.g. C-M-s [[:space:]]abcDEF
.
That includes the whitespace in the search hit. If you want to be able to see the word itself highlighted differently from the total match, use library isearch+.el
and search with this: C-M-s [[:space:]]\(abcDEF\)
. Isearch+ highlights each regexp group (e.g. \(...\)
) differently.