Смысл: -a

-a[-ə]
suff
<Í> образует форму мн. ч. лат. и греч. сущ. среднего рода, преим. научных терминов (особ. в области биологии)
1. соотносится с -um, суффиксом ед. ч. лат. сущ.:
herbaria - гербарии
sera - сыворотки
phyla - (таксономические) типы
spectra - спектры
scrota - мошонки
incunabula - инкунабулы
media - средства, среды
symposia - симпозиумы
bacteria - бактерии
формы на -a часто имеют параллельные варианты на -ums:
aquaria, aquariums - аквариумы
premia, premiums - надбавки, премии
millenia, milleniums - тысячелетия
2. соотносится с -on, суффиксом ед. ч. греч. сущ.:
criteria - критерии
phenomena - явления
noumena - ноумены
prolegomena - пролегомены
automata - автоматы
etyma - этимоны
3. часто встречается в названиях высших биологических таксонов (не имеющих форм ед. ч.):
Arthropoda - членистоногие
Amphibia - земноводные
Coelenterata - кишечнополостные
Chiroptera - рукокрылые
Hydrozoa - гидроиды
Monotremata - однопроходные

sigh of relief, (heave) a Идиома

a babe in arms

a baby, a child who is still wet behind the ears Dar was just a babe in arms when we emigrated to Canada.

a babe in the woods

"a defenseless person; a naive, young person" He's just a babe in the woods. He needs someone to protect him.

a bad taste in my mouth

a feeling that something is false or unfair, a feeling of ill will I left the meeting with a bad taste in my mouth. There was a lot of dishonesty in the room.

a bad time

a lot of teasing, a rough time The class gave him a bad time about his pink shorts.

a ball-park figure

"a number that is near the total; approximate figure" Fifty is a ball-park figure. It's close to our class size.

a bar fly

a person who often goes to bars or lounges Every evening Penny goes to Lucifer's. She's quite a bar fly.

a bar star

a girl who goes to bars to drink and find friends Lola was known as a bar star at Pinky's Lounge.

a bare-faced lie

a deliberate lie, a planned lie His statement to the police was false - a bare-faced lie.

a barnburner

an exciting game, a cliff-hanger When the Flames play the Oilers it's a barnburner - a great game.

a barrel of laughs

a lot of fun, a person who makes you laugh Let's invite Chang to our party. He's a barrel of laughs.

sigh of relief

A activity or affectation of abatement that article decidedly stressful, unpleasant, or abominable has been abhorred or completed. Everyone in chic heaved a blow of abatement afterwards that abhorrent midterm assay was over. Investors in Europe had a big blow of abatement now that a Greek avenue from the Euro has been avoided.Learn more: of, relief, sigh