On a generalization of weak flatness

Laan in Pullbacks and flatness properties of acts I, [Commun. Algebra 29(2) (2001) 829–850] introduced Condition [Formula: see text], a generalization of Condition [Formula: see text]. Golchin and Mohammadzadeh in [On Condition ([Formula: see text]), Semigroup Forum 86(2) (2012) 413–430] introduced Condition [Formula: see text], a generalization of Condition [Formula: see text]. In this paper similarly, we introduce a generalization of weak flatness property, called [Formula: see text], and will classify monoids by this property of their acts. We also characterize [Formula: see text] coherent monoids in general and monoids coming from some special classes.