1)Jettison, is a noun, deriving etymologically from Latin jacere, that means 'throw, in this case here the word means 'throw cargo into the sea, describing this same act of jacere'=throw etc

2)Job= Kind of work, profession, thus saying 'practice a job'=kind of work or business one does, for ex. 'Lawyer' is 'legal job' etc.

3)Join=verb that means 'become member',for ex. 'join a group' become member of group or team etc, or join a club=become member of a club, participate in its activities

4)Joint=corporate (εταιρικός), συνεταίρος (partner), 'joint action'=συνδυασμένη αγωγή, for ex. 'practice lawsuit in combined legal issues, for ex. a set of legal issues alltogether in one basic claim, that includes more/additional claims, to same person

Also we have a jojnt creditor or joint debtor=when two persons lend (in first case, thus give credit), or two debtors of a loan together. -Also 'joint holder'=συγκάτοχος, 'joint owner'=συνιδιοκτήτης, etc. Also 'joint guardian'συνεπίτροπος, for ex. when two persons together, become 'guardian of a non adult', if for ex. this non-adult, child, young person have no parents for ex. and have a fortune, that is controlled and managed by 'guardian', appointed by Court, on basis of decision, and who guardian, make decisions on this non adult person, on issues of his/her life, until he/she becomes adult etc

Also, with 'joint'=joint stock company=μετοχική εταιρεία, joint account, a bank account that belongs to two different persons, being both 'joint holders of account'=Also, 'Joint community'=κοινοπραξία, (non profit organization, persons joined together, that undertake acts on behalf of mun. community for ex.within a joint purpose..)

And finally 'joint criminal enterprise'=οργανωμένο έγκλημα..etc