  Let $x_\alpha$ be a net in a locally solid vector lattice $(X,\tau)$; we say
that $x_\alpha$ is unbounded $\tau$-convergent to a vector $x\in X$ if $\lvert
x_\alpha-x \rvert\wedge w \xrightarrow{\tau} 0$ for all $w\in X_+$. In this
paper, we study general properties of unbounded $\tau$-convergence (shortly,
$u\tau$-convergence). $u\tau$-Convergence generalizes unbounded norm
convergence and unbounded absolute weak convergence in normed lattices that
have been investigated recently. Besides, we introduce $u\tau$-topology and
study briefly metrizabililty and completeness of this topology.
