To mark items on a list (with a checkmark or by crossing them out) that have been chosen for keeping or removal or that have been dealt with (for example, completed or verified as correct or satisfactory); to tick off (UK), tick (UK), cross off, strike off.
To carry out a decision recorded through the process of checking off an item on a list, including dealing with it, removing it from the possible choices, or removing the not checked items from further consideration.
To deduct union members' dues from their wages.
To mark (important passages of text), e.g. with a fluorescent marker pen or in a wordprocessor, as a means of memory retention or for later reference.
To be a highlight of.
To make prominent; emphasize.
To seek the attention of (a user) on IRC by mentioning their name in a message, causing that message to appear highlighted on their screen.
To dye (part of the hair) a different color than the rest.
An area or a spot in a drawing, painting, or photograph that is strongly illuminated.
An especially significant or interesting detail or event or period of time.
A strand or spot of hair dyed a different color than the rest.