\begin{tabbing}
w{-}atom{-}constraint($w$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$\=($\forall$$i$, $x$:Id. AtomFree(Type;$w$.T($i$,$x$)))\+
\\[0ex]\& ($\forall$$i$, $a$:Id. AtomFree(Type;$w$.TA($i$,$a$)))
\\[0ex]\& ($\forall$$l$:IdLnk, ${\it tg}$:Id. AtomFree(Type;$w$.M($l$,${\it tg}$)))
\-
\end{tabbing}