Le mot clé **Mots « Mots clés :** : » et sa traduction sont des éléments d'une liste de type *description*.
Il faut donc demander à ce que cette liste ne soit pas indentée automatiquement.
C'est possible avec le package `enumitem` et l'option `[\labelindent=xcm]`, avec x une entrée numérique.
On aura alors par exemple :
\documentclass[mainlanguage=french]{yathesis}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{enumitem}
\makeatletter
\def\YAD@mainlanguage{english}
\expression{meta-abstract}{abstract1}{abstract2}%modification de l'esxpression par défaut
\renewcommand{\YAD@abstract@page}{%
\bgroup%
\enlargethispage{2cm}%
\setlength{\parindent}{0pt}%
\begin{minipage}{\linewidth}
\small%
{%
\bfseries%
\YAD@ifemptyorundef{\printtitle}{%
\YAD@generic@argument@translate{title}%
}{%
\textsc{\printtitle}%
}%
\ifundef{\printsubtitle}{%
}{%
\newline%
\printsubtitle%
}%
\vspace{-.5em}%
\vspace{\z@}%
\begin{center}%
\YAD@abstractname@mainlanguage%
\end{center}%
}%
\par%
\ifboolexpr{%
bool {YAD@abstract@used}%
and not bool {YAD@main@abstract@empty}%
}{%
\usebox{\YAD@abstract@mainlanguage}%
}{%
\YAD@generic@argument@translate{abstract}%
}%
\ifundef{\printkeywords}{%
}{%
\vspace{.5em}%
\begin{description}[labelindent=0cm]
\item[\YAD@translation{keywords}\IfLanguageName{french}{\ifundef{\Fcolonspace}{\FBcolonspace}{\Fcolonspace}}{}:]
\printkeywords
\end{description}
}%
\end{minipage}%
\ifbool{YAD@second@abstract@used}{%
\expandafter\selectlanguage\expandafter{\YAD@secondarylanguage}%
\\[.5\baselineskip]%
\YAD@abstract@page@rule%
\\[.5\baselineskip]%
\begin{minipage}{\linewidth}
\small%
{%
\bfseries%
\YAD@ifemptyorundef{\printtitle}{%
\YAD@generic@argument@translate{title}%
}{%
\textsc{\printtitle}%
}%
\ifundef{\printsubtitle}{%
}{%
\newline%
\printsubtitle%
}%
\vspace{-.5em}%
\vspace{\z@}%
\begin{center}%
\YAD@abstractname@secondarylanguage%
\end{center}%
}%
\par%
\ifboolexpr{%
bool {YAD@abstract@used}%
and not bool {YAD@second@abstract@empty}%
}{%
\usebox{\YAD@abstract@secondarylanguage}%
}{%
\YAD@generic@argument@translate{abstract}%
}%
\ifundef{\printkeywords}{%
}{%
\vspace{.5em}%
\begin{description}[labelindent=0cm]
\item[\YAD@translation{keywords}\IfLanguageName{french}{\ifundef{\Fcolonspace}{\FBcolonspace}{\Fcolonspace}}{}:]
\textnormal{\printkeywords}
\end{description}
}%
\end{minipage}%
}{%
}%
\\[.5\baselineskip]%
\YAD@abstract@page@rule%
% \par%
% \textbf{\printlaboratory*}%
% \\%
% \let\YAD@ORI@doublebackslash\\%
% \renewcommand{\\}{ -- }%
% \printlaboratoryaddress%
% \let\\\YAD@ORI@doublebackslash%
\egroup%
}%
\makeatother
\begin{document}
\begin{abstract}
blabla
blabla
\end{abstract}
\makeabstract
\end{document}
