In everyday language, 'quick' and 'speedy' are often used synonymously.

synonymously 是副词，由名词 synonym（同义词）加上形容词后缀 -ous（表示"具有...性质的"）构成形容词 synonymous（同义的），再加上副词后缀 -ly 构成。意思是"作为同义词地、可互换地"。