畢業典禮, 學位服 (commencement/convocation & academic dress/academic regalia)
六月是畢業季節，包括 Wikipedia 在內的許多網站都介紹 “The graduation ceremony itself is also called commencement, convocation or invocation.” (畢業典禮又叫做 commencement, convocation or invocation.) 不過 invocation 作為「畢業典禮」的說法不知有何根據？連完全本的 Merriam-Webster Unabridged 的invocation 詞條下都未見收錄這個意思。
如果搜尋 Google Ngram Viewer，「畢業致詞」的英文說法照頻率高低依次為：commencement speech, graduation speech, convocation speech，但找不到 *invocation speech (Ngrams not found: invocation speech)。(見圖 1)
畢業典禮何以叫做 commencement？因為以往大學畢業就要踏入社會工作。(We call it commencement because it marks the beginning of students' new lives in the world, the beginning of their professional life.)
畢業典禮又叫做 convocation ceremony 是台灣一般人較陌生的。見以下的一段文字： “Graduation ceremony or convocation ceremony is the most delightful event in a student's life as it marks the end of the student life and beginning of a new episode of working adults …” (www.dgreetings.com/gift-ideas/.../graduation-ceremony.html)
不過 convocation 除指大學裡的畢業典禮，有些學校也用來指新學年的開學典禮或頒獎典禮 “an assembly of the members of a college or university to observe a particular ceremony (as the opening of the academic year or the announcing of prizes, awards, and honors)” (Merriam-Webster Unabridged)
「準畢業生」英文有個專屬的詞，叫 graduand /ˈɡradʒʊənd/，Before graduation, candidates are referred to as graduands.
畢業典禮上穿的學位服 (academic dress/academic regalia/convocation dress) 是由學位袍/畢業袍 (academic gown/graduation gown)，四方帽 (square academic cap/mortarboard: a square board fixed upon a skull-cap, with a tassel 流蘇/繐子 attached) 等構成。
最後要特別注意，學位服至少有三四種說法，但不叫 graduation dress，如你 Google，會發現表面上似乎 "graduation dress" 比較多筆：
"graduation dress" site:uk 約有 880,000 項結果 (Google, 6/13/19)
"graduation gown" site:uk 約有 92,800 項結果
"convocation dress" site:uk 約有 1,700 項結果
但 graduation dress是指女生在畢業日學位服裡面或畢業派對上穿的洋裝，不是畢業袍。(Jerome Su, 6/17/19)
