The super-strong liquid left at the bottom of your mug after a teabag has been left in your now drunken tea. This usually occurs as a result of failure to completely drink the beverage or dispose of the teabag beforehand.
This is a code word used in situations, such as in the presence of parents, when it is inappropriate to say the word 'semen'. Mostly used in place of the word 'come' to disguise the nature of the conversation.
Bob - " Hey mate.. why did you spend 20 minutes staring at that orange juiceyesterday? "
Fred - " Because I uber-concentrated on the word concentrate "