プログレッシブ和英中辞典(第4版)の解説
しつよう【執×拗】
〔頑固〕obstinacy；〔しつこさ〕persistence；〔粘り強さ〕tenacity
執拗な（に） obstinate(ly); persistent(ly); tenacious(ly)
彼らは領土問題で執拗に食い下がった
They persisted in asking questions about the territorial problem.／They kept harping on the territorial question.
彼は執拗に自分の意見にこだわる
He clings obstinately [tenaciously] to his opinions.
彼女に執拗につきまとった
He 「followed her everywhere [stuck to her] like a shadow.／He stalked her.