1. (noun) something or someone that causes anxiety; a source of unhappiness

• concern
• vexation
• worry

2. (noun) pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs

• cephalalgia
• head ache

1. (noun) something or someone that causes anxiety; a source of unhappiness

• negative stimulus

2. (noun) pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs

• ache
• aching

1. (noun) something or someone that causes anxiety; a source of unhappiness

• bugaboo
• burden
• encumbrance
• incumbrance
• load
• onus
• business

2. (noun) pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs

• cluster headache
• histamine headache
• hemicrania
• megrim
• migraine
• sick headache
• sick headache
• sinus headache
• tension headache

1. (noun) something or someone that causes anxiety; a source of unhappiness

• care
• worry
• concern
• interest
• occupy
• worry
• vex
• vex
• worry
• worry
• worry