Dictionary definition · tick
noun
- a metallic tapping sound"he counted the ticks of the clock"
- any of two families of small parasitic arachnids with barbed proboscis; feed on blood of warm-blooded animals
- a mark indicating that something has been noted or completed etc."as he called the roll he put a check mark by each student's name"
- a light mattress
verb
- make a clicking or ticking sound"The clock ticked away"
- make a sound like a clock or a timer"the clocks were ticking"
- sew"tick a mattress"
- put a check mark on or near or next to"Please check each name on the list"
Source: Open English WordNet (CC BY 4.0).