six 
/ˈsɪks/ noun
plural sixes /ˈsɪks/ noun 1 [count] : the number 6 2 [count] : the sixth in a set or series
▪ the six of hearts 3 [noncount] : six o'clock
▪ “What time is it?” “It's six.” ▪ I leave each day at six.
▪ the six of hearts
▪ “What time is it?” “It's six.” ▪ I leave each day at six.
at sixes and sevens
chiefly Brit, informal : disorganized and confused
▪ The change left everyone at sixes and sevens. ▪ Everything will be at sixes and sevens until our computer system is fixed.
▪ The change left everyone at sixes and sevens. ▪ Everything will be at sixes and sevens until our computer system is fixed.
hit/knock (someone) for six
Brit, informal : to have an unpleasant and shocking effect on (someone)
▪ The news of the accident really hit me for six.
▪ The news of the accident really hit me for six.
six of one, half (a) dozen of the other (US) or chiefly Brit six of one and half a dozen of the other
informal — used to say that you do not see any real difference between two possible choices ▪ “Which do you prefer?” “I don't care; it's six of one, half a dozen of the other.”
— six adjective
▪ six possibilities/hours
▪ six possibilities/hours
— six pronoun
▪ Six (of them) will be coming tonight.
▪ Six (of them) will be coming tonight.
