Caitriona O’Reilly’s poems offer readers elaborate, richly worked lines as well as engaging, if trickily presented, arguments. The poems of her third book, Geis (Bloodaxe, £9.95) are often etymological as they dig down into their subject, and she imports a word for her title, which she defines as a “word from Irish mythology meaning a supernatural taboo or injunction on behaviour”.

Its first poem, Ovum, does not reference "ubh" in its seemingly associative dwelling on the title's meaning: "You'd take it for zero, or nothing, / or the spotless oval your lips make saying it", the poem begins, before O'Reilly begins one of her typically extravagant speculations,

as if you blew both yolk and albumen

through its pin-pricked head: the meat

of the word made orotund and Latinate.

It’s like putting your mouth to the smooth

breast of the ocarina, from oca, the goose,

hooting out its fledgling notes.

The title and method will remind readers of Seamus Heaney's Alphabets, whose astronaut sees "all that he has sprung from, / The risen, aqueous, singular, lucent O / Like a magnified and buoyant ovum", although as O'Reilly counts out other O-words that occur to her she introduces a very different figure:

the death-mark, dagger or crucifix,

as phallic and obvious, now that you say it,

as that double o in spermatozoon,

which enters by its own locomotion –

the flagellum, its tiny whip and scourge.

Sex and sexuality in other poems are equally fraught: the aphrodisiac Spanish Fly is “Not glass-green at all but iridescent, / a mineral-winged insect pulverised // with toads’ bones, moles’ teeth and iron filings; / a glittery suspension I give him to drink”, while nightmarish restlessness extends more broadly to a natural world inhabited by Amanita Virosa, “a fruiting / blue-white, white gilled body: erotic, // spilling its fine white powders; its pale spore print the negative / of a moth’s dense-celled wing.”

This is an imagination that is darkly, vividly creative, occasionally calling to mind the great Irish-American poet Marianne Moore, but Geis also strikes another, plainer note: "A skin of rubber // saves us from each other. / Nothing gets through, but at night the traitor body // dreams itself full / of death-in-life / and life-in-death" (Empty House). The title sequence recounts the torments of an enveloping sickness, "two months in a sweat-soaked hospital bed" (Riddle), the "radiant stone placed on the tongue", "getting the cramped brain to release its grip" (O), and finds in the story of Jonah some way of comprehending the descent into illness it describes:

The clattering backwash and undertow of a life!

A darkness swallowed me whole.

I subsisted in its guts, in a foetal coil,

My skin blanched by its acids,

My limbs attenuated as a seedling kept from the light.

It was no gothic, ringing interior, this;

I was held close, familiar.

Its tissues muffled my cries.

(Jonah)

Snow is one of a number of poems here that reflect on a sort of "vast, multitudinous silence", but if silence haunts the margins of O'Reilly's poems, that Latinate polysyllabic multitudinous is just as defining of her poems' ambitious music. Bee on Agastache draws on vocabulary associated with bees and flowers to offer an unusual, winning portrait of the artist: "It is our calling to be lost in detail," the poem begins, before it pieces together its unusual sounds,

the peduncle with its cunning bracts, ramified

for the parsing of winged grammarians;

we thrive in the trickery of constructions,

in the manner of address, entry,

the faint trace of civet that was left:

the flower

matches our obsessions exactly.

The poems in Doireann Ní Ghríofa’s Clasp (Dedalus, €11.50) have their own force, and an unusual provenance.

Ní Ghríofa has shifted language, having already published two books of poems in Irish with Coiscéim, and Maeve in Chile teases out questions of language and strangeness over a meal of

potatoes with lengua: You wait for me

to grimace like the other gringos, but

I smile.

I know the shape of a dead tongue in my mouth,

strong muscle meat, grey, heavy. I cut a chunk.

The root is thicker, tougher than I remember,

and when it slides down my throat, I think of home

Ní Ghríofa often mixes matter-of-fact narration with more symbolic language which jump-starts our understanding of the poems' scenes: The Horse Under the Hearth offers a gloss on Eibhlín Dubh Ní­ Chonaill's life after her famous poem, remembering the horse for which Art Ó Laoghaire was arraigned: "Everyone knows what happened then, I versed it strong / and spoke it often. But what of her? / Her neck, like mine, knew the rough stubble of his cheek [ . . . ] // And so, her head came back."

The book's three sections show Ní Ghríofa trying out various tones and forms, and the poems often discover as their territory the faultline between fixed forms and living speech, as when Triolet for the keeper of childhood memories adopts a conversational tone, ending, "No, no, your costume was blue. Yes I am sure. For God's sake! / You must remember that day." And one of her Seven Views of Cork City, a sort of autobiography, is set in Tesco, where it reports on the kind of world and "lonely voice" often left to short fiction:

I walked up

and down aisles with my broad bristled brush

past tired midwives in blood-spattered scrubs, then out

to the dark car park to gather stray trollies

and slot them into each other, steel in steel,

tucked in neatly to dream of speed.

John McAuliffe's fourth collection is The Way In (Gallery). He teaches poetry at the University of Manchester's centre for new writing