'Weaker' in the Bible

The battle [was] prolonged between the house of Saul and the house of David, but David {[was] growing stronger and stronger} while the house of Saul {[was] becoming weaker and weaker}.

But by much more the members of the body which are thought to be weaker are necessary,

Husbands, in the same way live with [your wives] {knowledgeably}, as with the weaker female vessel, showing [them] honor as fellow heirs also of the grace of life, so that your prayers will not be hindered.