A foreign body in the eye is a small object which enters and gets stuck in the eye. This may be something which sticks to the front of the eye or gets trapped under the eyelids without actually entering the eye.
Symptoms of a foreign body in the eye will include pain and a gritty feeling of something stuck in the eye. The eye will water considerably and vision is likely to be impaired.
It is very common to get a small piece of grit, sand, dust or even an eyelash stuck in the eye. This happens when something is blown into the eye, for example on a windy day, or when something falls into the eye when we are looking upwards.
Objects which actually enter the eye are less common. They occur when people are hammering at something such as wood or metal and a small chip flies off and into the eye. In many cases, whilst this is a more serious injury it is not as painful.
Rinse the eye with warm water to try to rinse out the object. Don't stick anything (like a cotton bud etc) into the eye as this could cause further damage. If this doesn't work or if you continue to get symptoms, consult a doctor. If you suspect that something entered your eye, seek medical attention as soon as possible.