farther
[adverb]
Synonyms: beyond, further, yon, yonder
[adjective]
Synonyms: additional, added, another, else, fresh, further, more, now, other

[TahlilGaran] English Synonym Dictionary ▲

I. far‧ther¹ /ˈfɑːðə $ ˈfɑːrðər-/ adverb

1. a greater distance than before or than something else; a comparative form of ‘far’ Synonym : further:
We decided not to go any farther.
farther away/apart/down/along etc
The boats were drifting farther and farther apart.
a resort town farther up the coast
farther south/north etc
Two miles farther south is the village of Santa Catarina.
Most of them were locals, but some had come from farther afield (=a greater distance away).

2. if you do something farther, you do it more or to a greater degree Synonym : further:
We’d better investigate farther.
The police decided not to take the matter any farther (=do more about it).

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In everyday English, people usually say further rather than farther, and furthest rather than farthest:
We decided not to take it any further.
This was the furthest away from home I’d ever been.

[TahlilGaran] Dictionary of Contemporary English ▲

II. farther² adjective [only before noun]
more distant; a comparative form of ‘far’ Synonym : further:
A table stood at the farther end of the kitchen.

[TahlilGaran] Dictionary of Contemporary English ▲