There is no one, single such resource. Often it takes a lot of work. You can start with Online Etymology, good for basics. However, it won't list the second meaning of catamaran, as is also the case for many dictionaries, because it was a colloquilalism used around the turn of the last century.
Dictionary.com defines it: 3. (old-fashioned) a quarrelsome woman, as does Collins, but no origin is given. Merriam Webster and some others doesn't list it at all.
The word catamaran was introduced into the English language by the explorer/naturalist/buccaneer William Dampier (1651–1715).
Brewer's Dictionary of Phrase & Fable lists it as
A colloquial term for a quarrelsome old woman, so called from a pun on ‘cat’.
The closest to origins that I could come are a guess based on a Wikipedia entry for fish wife, and a really obscure book. From Wikipedia:
Often the wives and daughters of fishermen, fish wives were notoriously loud and foul-mouthed, as noted in the expression, To swear like a fishwife. One reason for their outspokenness is that their wares were highly perishable and so lost value if not sold quickly. In the 18th century, fishwives frequently appeared in satires as fearsome scourges of fops and foreigners. Their vigorous and decisive mien was contrasted with that of politicians who were, by contrast, portrayed as vacillating and weak. For example, in Isaac Cruikshank's A New Catamaran Expedition!!!, a fleet of fishwives sails across the Channel to terrify the French and shame the Prime Minister, William Pitt.
This was published by Wm. Holland in 1805. Clearly by then, fishwives were referred to as catamarans even though their boat clearly is not.
From SLANG ANALOGUES PAST AND PRESENT. A DICTIONARY, HISTORICAL AND COMPARATIVE, OF THE HETERODOX SPEECH OF ALL CLASSES OF SOCIETY FOR MORE THAN THREE HUNDRED YEARS. WITH SYNONYMS IN ENGLISH, FRENCH, GERMAN, ITALIAN, ETC. (caps not mine) COMPILED AND EDITED BY JOHN S. FARMER and W. E. HENLEY. VOL. II. C. TO Fizzle
First, they address (under catamaran) the words "Cat in a pan":
4 Lett. Conf., in wks. (Grosart) II., 286. If it bee a home booke at his
first conception, let it be a home booke still, and TURNE NOT CAT IN THE PANNE.
BACON, Essays (of Cunning), p. 441 (Arber). There is a Cunning, which we in England call, The TURNING OF THE CAT IN THE PAN, which is, when that which a Man says to another, he laies it, as if Another had said it to him.
c. 1720. Song, The Vicar of Bray. "When George in pudding time came in/ And moderate men looked big, sir/ He TURNED A CAT-IN-PAN once more/ And so became a Whig, sir."
- SCOTT, Old Mortality, ch.xxxv. "O, this precious Basil will TURN CAT IN PAN with any man !" replied Claverhouse.
phr. (popular). To 'have a mouth' after drunkenness.
CATAMARAN, subs, (colloquial). A vixenish old woman ; also a cross- grained person of either sex. _Cf., CATAMOUNT. Probably associated with the colloquial use of CAT, a quarrelsome, vicious woman]. For synonyms, see GEEZER.
MARRY AT, Peter Simple, ch. vi. The cursed drunken old CATAMARAN, cried he, I'll go and cut her down by the head.
THACKERAY. Nevucomes, ch.Ixxv. "What a woman that Mrs. Mackenzie is!" cries F.B. "What an infernal tartar and CATAMARAN!"
Macmillan's Magazine, June, p. 113. She was such an obstinate old CATAMARAN.
CATAMOUNT, C ATA MOUNTAIN, or CAT O' MOUNTAIN, subs. (American). A shrew [see above CATAMARAN and Beaumont and Fletcher's use of the word for a wild man from the mountains, itself a transferred sense of catamount = a leopard or panther.]
FLETCHER, Cust. of Country, I., i. The rude claws of such a CAT o' MOUNTAIN!
HALIBURTON, Clockmaker, i S., ch., xii. She was a dreadful cross-grained woman, a real CATAMOUNT, as savage as a she-bear that has cubs.
So you see, it's not that easy. Easy ones are easy to find. The hard ones (like this one) take a lot of searching, especially when the word has fallen out of usage.