Low and Second string

Low adjective - Being near the equator.

Second string and low are semantically related. In some cases you can replace phrase "Second string" with "Low", this terms are similar.

Second string noun - A squad of players that are available either individually or as a team to relieve or replace the players who started the game.

Low and second string are semantically related. Sometimes you can use "Low" instead an adjective phrase "Second string".