To Add Something To
To Include Something, To Accompany, To Garnish
transitive verb, ichidan verb
Because the hiragana ends with an う sound, you know this word is a verb. When appending something, you basically want to add something to something, or to include something with it.
添える means to add something alongside the main thing, often as a thoughtful touch to complement or support it. For example, you might say 添える when including a letter with a gift to add a personal touch, or when garnishing a dish with parsley to enhance its appearance. It's also used when you feel inclined to add a second hand to hold a bowl carefully.
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you: One way to add something to something else is to just sew (そ) it on!
そのシェフは、ステーキにバニラアイスクリームを添えた。
The chef garnished the steak with some vanilla ice cream.