We introduce a generalization of algebraic compactness for modules ana
logous to, and extending the one given for abelian groups by C. Megibb
en in [13]. After a preliminary section, we discuss the relationship b
etween this notion and the matrix subgroups of W. Zimmermann [17], and
then use the results obtained to generalize, through a filter-theoret
ic approach, several theorems of W. Zimmermann [17] and E.M. Martinet
[11].