1. A form of daylight-saving time, one hour ahead of UTC, used in the United Kingdom, Ireland and mainland Portugal in summer
   - British Summer Time, BST, Western European Summer Time

Encyclopedia: Irish Standard Time

• iodine
• iodine-125
• iodine-131
• iodise
• iodised
• iodize
• iodized
• iodoamino acid
• iodochlorhydroxyquin
• iodocompound
• iodoform
• iodoprotein
• iodopsin
• iodothyronine
• iodotyrosine
• IOL
• ion
• ion beam
• ion engine
• ion exchange
• ion pump
• ionate
• Ionesco
• Ionia
• Ionian