roper (n.)

Middle English rop, from Old English rap "strong, heavy cord of considerable thickness," from Proto-Germanic *raipaz (source also of Old Norse reip, West Frisian reap, Middle Dutch, Dutch reep "rope," Old Frisian silrap "shoe-thong," Gothic skauda-raip "shoe-lace," Old High German, German reif "ring, hoop"). Technically, only cordage above one inch in circumference and below 10 (bigger-around than that is a cable). Nautical use varies. Finnish raippa "hoop, rope, twig" is a Germanic loan-word.

It is attested by early 14c. as "a noose, a snare." Rope of sand (1620s) was an old figure for anything lacking coherence or binding power.

To know the ropes "understand the way to do something" (1840, Dana) originally was a seaman's term. The phrase on the ropes "about to be defeated" is attested from 1924, a figurative extension from the fight ring, where being in or on the ropes was a figure by 1829.

To be at the end of (one's) rope "out of resources and options" is attested by 1680s. An earlier expression was have too long rope "have too much freedom" (late 15c.).

Rope formerly also figured in slang and extended-sense expressions related to punishment by hanging, such as John Roper's window "a noose," rope-ripe "deserving to be hanged," both 16c. The figurative phrase give someone (enough) rope (to hang himself) is by 1680s.

English agent noun ending, corresponding to Latin -or. In native words it represents Old English -ere (Old Northumbrian also -are) "man who has to do with," from Proto-Germanic *-ari (cognates: German -er, Swedish -are, Danish -ere), from Proto-Germanic *-arjoz. Some believe this root is identical with, and perhaps a borrowing of, Latin -arius (see -ary).

Generally used with native Germanic words. In words of Latin origin, verbs derived from past participle stems of Latin ones (including most verbs in -ate) usually take the Latin ending -or, as do Latin verbs that passed through French (such as governor); but there are many exceptions (eraser, laborer, promoter, deserter; sailor, bachelor), some of which were conformed from Latin to English in late Middle English.

The use of -or and -ee in legal language (such as lessor/lessee) to distinguish actors and recipients of action has given the -or ending a tinge of professionalism, and this makes it useful in doubling words that have a professional and a non-professional sense (such as advisor/adviser, conductor/conducter, incubator/incubater, elevator/elevater).