A model or type of machinery or device which precedes the current (or later) one. Usually used to describe an earlier, outdated model.
One who precedes; one who has preceded another in any state, position, office, etc.; one whom another follows or comes after, in any office or position.
A vertex having a directed path to another vertex
To act as an understudy (to someone).
To study or know a role to such an extent as to be able to replace the normal performer when required.
To act in a similar manner to some known person.
A performer who understudies; a standby.