deep

n.

[1]	trench , oceanic abyss
[2]	the deep , the ocean , the main , the sea , the waters , the high seas , the briny (deep) , the wave(s) , Davy Jones's locker , Neptune's/Poseidon's kingdom/domain

adv.

[1]	deeply , far down , profoundly , intensely , earnestly , heavily
[2]	deeply
[3]	late

adj.

[1]	extensive , bottomless , abyssal , unfathomable , profound , wide , broad , yawning , chasmal/chasmic
[2]	profound , arcane , recondite , difficult , abstruse , obscure , esoteric , incomprehensible , beyond/past comprehension , impenetrable , unfathomable , inscrutable , mysterious , mystic(al) , occult , weighty , serious , (Colloq) heavy
[3]	wise , learned , sage , sagacious , astute , perspicacious , profound , discerning , acute , intense , penetrating , knowledgeable , knowing
[4]	rapt , absorbed , engrossed , occupied , preoccupied , intent , intense , involved , engaged , immersed , lost , (Colloq) into
[5]	devious , cunning , shrewd , crafty , canny , clever , knowing , scheming , artful , designing
[6]	profound , intense , sincere , serious , heartfelt , earnest , ardent , fervent , poignant , deep-rooted
[7]	low , resonant , booming , resounding , sonorous , rumbling
[8]	rich , dark , intense , strong
[9]	bass
[10]	rich
[11]	thick
[12]	cryptic , cryptical , inscrutable , mysterious , mystifying
[13]	abstruse , recondite