There is a Female Version of Phallic Imagery
Whether he liked it or not, Sigmund Freud made a lot of contributions to the field of phallic symbols. Even today, some individuals really question whether a cigar is merely a cigar. There have been many words in books and articles devoted to whether or not that implies anything. Anything that is vaguely shaped like a penis might be labeled a phallic symbol. Skyscrapers, cars, and even guns have all been referred to as phallic symbols at various points in history. Perhaps there is some psychology at work here. Or perhaps a shape that is longer than it is wide is just quite typical.
Despite all the discourse about phallic symbols, it is important to remember that there is also a negative aspect to the phrase since it clearly alludes to a certain gendered image. Anything that may be compared to female genitalia is referred to be yonic imagery, which is the female equivalent.
The word for womb in Sanskrit is yoni, which gives rise to the name. It was frequently compared to things like flowers, a metaphor that is still used today and can be seen in paintings that have been stylized to depict the female anatomy.