cos
n.n. a short, informal way of saying 'because'. You use it in casual speech or text messages when you want to give a reason for something.
n. a clipped or apocopated form of 'because', used to introduce a clause that provides a reason or explanation. Restricted to informal spoken registers and casual digital communication.
I'm staying home 'cos I'm tired.
We didn't go to the beach 'cos the weather forecast predicted heavy rain all afternoon.
The director chose to film in black and white 'cos he felt it captured the bleak atmosphere of the novel more effectively than color ever could.
Often written with an apostrophe ('cos) to indicate the missing first syllable, though 'cos' or 'cause' are also common in informal writing.
I stayed home cos of the rain.I stayed home because of the rain.While 'cos' replaces the conjunction 'because', it is rarely used in the compound preposition 'because of' in standard writing; 'cos of' is considered highly non-standard.