Si scusa..mi sono espresso male.
Allora il preambolo è
`\documentclass[a4paper,12pt,oneside,draft]{article}
\usepackage{amsmath, amsfonts, amssymb}
\usepackage{graphicx}\graphicspath{{./fig}}
\usepackage{xypic}\input xy\xyoption{all}
%\usepackage{times}
\usepackage{geometry}
\usepackage[applemac]{inputenc}
\newtheorem{thm}{Theorem}[section]
\newtheorem{cor}[thm]{Corollary}
\newtheorem{lem}[thm]{Lemma}
\newtheorem{prop}[thm]{Proposition}
\newtheorem{defn}[thm]{Definition}
\newtheorem{rem}[thm]{Remark}
\newtheorem{ex}[thm]{Example}
\newenvironment{proof}{\textit{\textbf{Proof.}} \textrm}{$\Box$}
\newenvironment{Keywords}{\textbf{Keywords}:} {}
\newenvironment{Classification}{\textbf{AMS Classification}:}{}
\numberwithin{equation}{section}
\newcommand{\R}{\mathbb{R}}
\newcommand{\N}{\mathbb{N}}
\hyphenation{Coalition-al}`
poi scrivo nel documento
`
\begin{defn}
In the sa\-me settings of Definition \ref{main definition},
we say that $a$
bla bla bla
\end{defn}
`
Ma nessuno effetto cesura visualizzato nel pdf ottenuto per la parola
same
Ciao. Grazie.
F.