isearch-forward-symbol

isearch-forward-symbol is an interactive compiled Lisp function in `isearch.el'.

It is bound to M-s _.

(isearch-forward-symbol &optional NOT-SYMBOL NO-RECURSIVE-EDIT)

Do incremental search forward for a symbol.
The prefix argument is currently unused.
Like ordinary incremental search except that your input is treated
as a symbol surrounded by symbol boundary constructs \_< and \_>.
See the command `isearch-forward' for more information.