The Trick in Rhyming Sofas and Chauffeurs

I laid a small, silent, moneyless wager with myself when I brought ''The Penguin Rhyming Dictionary'' home. ''I bet,'' I said, ''that it doesn't list 'cotoneaster.' ''

To the horticulturally uninitiated, ''cotoneaster'' is a kind of climbing shrub with dark green leaves and red berries.

Confident of winning my bet, I looked it up in the index - and - blow me down - I was wrong! There it was: ''cotoneaster 17.379'' it said.

Under the number ''17'' were words ending in ''er'' (or sounding like ''er''). I turned to the appropriate section. But before I looked I said: ''OK, then, I bet the compiler doesn't mention Thomas Hardy's rhyme for 'cotoneaster.' ''

And this time I was right.

On the other hand, the rhymes that Rosalind Fergusson (the compiler) has grouped around ''cotoneaster'' are, in themselves, pretty incredible and obscure. They include such things as: Rasta; piastre (South Vietnamese currency); Jocasta (mother of Oedipus); pinaster (Mediterranean pine); Zoroaster (Persian prophet); and verticillaster (botany term). Also included - and it appears to have been appended without irony, though nothing is certain anymore - is the word ''poetaster,'' with the bracketed explanation: ''inferior poet.''

I would say the implication is clear: Anyone who even contemplates the possibility of writing a poem that includes any of the aforesaid rhymes runs the distinct risk of becoming an ''inferior poet'' - or, as The Oxford Dictionary defines the word, a mere ''rimester.'' Nevertheless, the temptation is terribly strong to attempt a poem that somehow brings together intelligibly a berried bush, Oedipus's maternal parent, a seer of Persia, and a South Vietnamese cash transaction. It is the stuff of British quiz shows. It is a challenge to the wit and silliness of man.

So I won't attempt it. It would certainly be a disaster - a word that in fact has more likelihood of rhyming satisfactorily with ''cotoneaster'' than ''poetaster,'' as it is commonly pronounced.

Who uses rhyming dictionaries?

The answer supplied by the author in her preface is itself quoted from an earlier rhyming dictionary, more than 150 years old, whose compiler claimed that his dictionary has ''been a friend in need to generations of poets and rhymesters from Byron downwards.'' Downwards is probably the operative word. A poet worth his or her salt is surely one to whom the rhyme - if used at all - comes out of head or air. Isn't there something cheating about having to look up a rhyme?

The most dismal, abysmal verse lays hefty emphasis on rhyme-endings as if they matter more than anything else, and the jejune Moon-June formula of slipshod ballads resides at the very bottom of the heap.

Yet, contrariwise, when rhyme is a barely noticeable element, it can bring a kind of inner certainty, a sort of weightless pattern of sound - or wit.

Some poets of wit have made great play with rhymes, have used them even to devastating, pointed effect:

''How dreary to be somebody!/How public, like a frog/To tell your name the livelong day/To an admiring bog.'' (Emily Dickinson)

And is the recluse of Amherst as many miles from Ogden Nash as serious poetomanes would like to think? Or to put it another way, isn't Nash - for all his taste in the absurd - a more serious poet than he is given credit for? Has anyone made a study of Nash lately? Perhaps I should lead the way:

If somebody hasn't already

Someone else most certainly should

(Working at it nice and steady)

Write a lengthy and erudite, not to say scholarly and good

Book or maybe it should be called a study

On the subtle and original rhymes of Ogden Nash.

It might bring in some cash.

Even if it didn't attract quite so many dollars, pounds, or piastres that the writer of such a thesis might justifiably be compared to Croesus.

Here are some ideas to make a start: observe the redoubtable Nash's use of rhyme in the following:

''Let us pause to consider the English,

Who when they pause to consider themselves they get all reticently thrilled and tinglish.'' (From ''England Expects.'')

Or: ''So I think it is very nice for ladies to be lithe and lissom

But not so much so that you cut yourself if you happen to embrace or kissom.'' (From: ''Curl Up and Diet.'')

Or:

Behold the duck.

It does not cluck.

A cluck it lacks.

It quacks.

(From ''The Duck.'')

Nash's rhymes are sometimes, to say the least, inventive. Who but Nash (unless it be Thomas Hardy with his cotoneaster) would rhyme ''gallows'' with ''aloes,'' ''sofa'' with ''chauffeur,'' ''anacondas'' with ''absconders,'' or ''meringue'' and ''boomerang,'' and.just about get away with it.

Oh, and if you have been wondering what rhymes with ''penguin,'' then this book of mine is little help. On ''puffin,'' however, it isn't half bad. It suggests ''muffin'' and ''ragamuffin.''

Well, they're better than nuffin.