ぜんしゃ前者zensha
1.

Refers to the first of two items mentioned in a comparison or discussion, distinguishing it from the latter item.

2.

Identifies the preceding element in a pair, emphasizing its relevance in the context of a contrasting relationship with another item.

3.

Denotes the earlier mentioned option when presenting two possibilities, contrasting it with the subsequent one.

Example:

いくつかの点で、前者は後者よりも劣っていると彼は指摘した。