What's the difference between further and furthermost?

Further

Definition:

• (adv.) To a greater distance; in addition; moreover. See Farther.
• (superl.) More remote; at a greater distance; more in advance; farther; as, the further end of the field. See Farther.
• (superl.) Beyond; additional; as, a further reason for this opinion; nothing further to suggest.
• (adv.) To help forward; to promote; to advance; to forward; to help or assist.

Example Sentences:

Furthermost

Definition:

• (a.) Most remote; furthest.

Example Sentences:

• (1) If a fixed partial denture must withstand loading outside these areas, as is the case with cantilevered pontics and some tilted abutments, the retainer furthermost from the anticipated eccentric load must have exceptionally good retention.